CUB-124 : scaffold Control Center Go backend

CUB-127 : implement Control Center CRUD API in Go
Merge pull request 'CUB-20 : Agent card component with dynamic status/progress' (#28) from agent/rex/CUB-20-agent-card-component into dev
2026-05-07 14:16:05 -04:00 · 2026-05-06 17:29:44 -04:00 · 2026-04-29 11:29:23 -04:00 · 2026-04-29 11:02:33 -04:00 · 2026-04-29 10:53:17 -04:00 · 2026-04-29 10:22:18 -04:00
41 changed files with 2658 additions and 505 deletions
--- a/frontend/.dockerignore
+++ b/frontend/.dockerignore
@@ -0,0 +1,33 @@
+# Dependencies
+node_modules/
+npm-debug.log*
+yarn-error.log
+
+# Build output (rebuilt in container)
+dist/
+out-tsc/
+
+# Angular cache
+.angular/cache/
+
+# IDE
+.idea/
+.vscode/
+*.sublime-workspace
+
+# OS files
+.DS_Store
+Thumbs.db
+
+# Git
+.git/
+.gitignore
+
+# Docker
+Dockerfile
+.dockerignore
+
+# Misc
+coverage/
+tmp/
+*.log
--- a/frontend/Dockerfile
+++ b/frontend/Dockerfile
@@ -0,0 +1,38 @@
+# ============================================================
+# Control Center Frontend — Multi-stage Docker Build
+# Angular 21 + nginx for static serving + API proxy
+# ============================================================
+
+# --- Build Stage ---
+FROM node:22-slim AS builder
+
+WORKDIR /app
+
+# Install dependencies first (layer caching)
+COPY package.json package-lock.json ./
+RUN npm ci
+
+# Copy source and build production bundle
+COPY . .
+RUN npm run build
+
+# --- Runtime Stage ---
+FROM nginx:1.27-alpine AS runtime
+
+# Remove default nginx config
+RUN rm /etc/nginx/conf.d/default.conf
+
+# Copy custom nginx config
+COPY nginx.conf /etc/nginx/conf.d/default.conf
+
+# Copy built Angular app from builder stage
+COPY --from=builder /app/dist/frontend/browser /usr/share/nginx/html
+
+# Expose HTTP port
+EXPOSE 80
+
+# Health check — confirm nginx is serving
+HEALTHCHECK --interval=30s --timeout=3s --start-period=5s --retries=3 \
+  CMD wget -qO- http://localhost/ || exit 1
+
+CMD ["nginx", "-g", "daemon off;"]
--- a/frontend/angular.json
+++ b/frontend/angular.json
@@ -56,7 +56,8 @@
            ],
            "stylePreprocessorOptions": {
              "includePaths": [
-                "src"
+"src",
+                "src/styles"
              ]
            }
          },
--- a/frontend/nginx.conf
+++ b/frontend/nginx.conf
@@ -0,0 +1,54 @@
+server {
+    listen 80;
+    server_name _;
+
+    root /usr/share/nginx/html;
+    index index.html;
+
+    # Gzip compression
+    gzip on;
+    gzip_vary on;
+    gzip_proxied any;
+    gzip_comp_level 6;
+    gzip_types text/plain text/css application/json application/javascript text/xml application/xml application/xml+rss text/javascript image/svg+xml;
+
+    # Cache static assets (Angular uses content hashes)
+    location /assets/ {
+        expires 1y;
+        add_header Cache-Control "public, immutable";
+    }
+
+    # Cache hashed JS/CSS bundles
+    location ~* \.(js|css)$ {
+        expires 1y;
+        add_header Cache-Control "public, immutable";
+    }
+
+    # Proxy API requests to backend
+    location /api/ {
+        proxy_pass http://backend:8080/api/;
+        proxy_http_version 1.1;
+        proxy_set_header Host $host;
+        proxy_set_header X-Real-IP $remote_addr;
+        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
+        proxy_set_header X-Forwarded-Proto $scheme;
+    }
+
+    # Proxy SignalR WebSocket connections to backend
+    location /hubs/ {
+        proxy_pass http://backend:8080/hubs/;
+        proxy_http_version 1.1;
+        proxy_set_header Upgrade $http_upgrade;
+        proxy_set_header Connection "upgrade";
+        proxy_set_header Host $host;
+        proxy_set_header X-Real-IP $remote_addr;
+        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
+        proxy_set_header X-Forwarded-Proto $scheme;
+        proxy_read_timeout 86400;
+    }
+
+    # Angular SPA — all other routes fall back to index.html
+    location / {
+        try_files $uri $uri/ /index.html;
+    }
+}
--- a/frontend/src/app/app.html
+++ b/frontend/src/app/app.html
@@ -1,344 +1 @@
-<!-- * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * -->
-<!-- * * * * * * * * * * * The content below * * * * * * * * * * * -->
-<!-- * * * * * * * * * * is only a placeholder * * * * * * * * * * -->
-<!-- * * * * * * * * * * and can be replaced.  * * * * * * * * * * -->
-<!-- * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * -->
-<!-- * * * * * * * * * Delete the template below * * * * * * * * * -->
-<!-- * * * * * * * to get started with your project! * * * * * * * -->
-<!-- * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * -->
-
-<style>
-  :host {
-    --bright-blue: oklch(51.01% 0.274 263.83);
-    --electric-violet: oklch(53.18% 0.28 296.97);
-    --french-violet: oklch(47.66% 0.246 305.88);
-    --vivid-pink: oklch(69.02% 0.277 332.77);
-    --hot-red: oklch(61.42% 0.238 15.34);
-    --orange-red: oklch(63.32% 0.24 31.68);
-
-    --gray-900: oklch(19.37% 0.006 300.98);
-    --gray-700: oklch(36.98% 0.014 302.71);
-    --gray-400: oklch(70.9% 0.015 304.04);
-
-    --red-to-pink-to-purple-vertical-gradient: linear-gradient(
-      180deg,
-      var(--orange-red) 0%,
-      var(--vivid-pink) 50%,
-      var(--electric-violet) 100%
-    );
-
-    --red-to-pink-to-purple-horizontal-gradient: linear-gradient(
-      90deg,
-      var(--orange-red) 0%,
-      var(--vivid-pink) 50%,
-      var(--electric-violet) 100%
-    );
-
-    --pill-accent: var(--bright-blue);
-
-    font-family: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
-      Helvetica, Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji",
-      "Segoe UI Symbol";
-    box-sizing: border-box;
-    -webkit-font-smoothing: antialiased;
-    -moz-osx-font-smoothing: grayscale;
-    display: block;
-    height: 100dvh;
-  }
-
-  h1 {
-    font-size: 3.125rem;
-    color: var(--gray-900);
-    font-weight: 500;
-    line-height: 100%;
-    letter-spacing: -0.125rem;
-    margin: 0;
-    font-family: "Inter Tight", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
-      Helvetica, Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji",
-      "Segoe UI Symbol";
-  }
-
-  p {
-    margin: 0;
-    color: var(--gray-700);
-  }
-
-  main {
-    width: 100%;
-    min-height: 100%;
-    display: flex;
-    justify-content: center;
-    align-items: center;
-    padding: 1rem;
-    box-sizing: inherit;
-    position: relative;
-  }
-
-  .angular-logo {
-    max-width: 9.2rem;
-  }
-
-  .content {
-    display: flex;
-    justify-content: space-around;
-    width: 100%;
-    max-width: 700px;
-    margin-bottom: 3rem;
-  }
-
-  .content h1 {
-    margin-top: 1.75rem;
-  }
-
-  .content p {
-    margin-top: 1.5rem;
-  }
-
-  .divider {
-    width: 1px;
-    background: var(--red-to-pink-to-purple-vertical-gradient);
-    margin-inline: 0.5rem;
-  }
-
-  .pill-group {
-    display: flex;
-    flex-direction: column;
-    align-items: start;
-    flex-wrap: wrap;
-    gap: 1.25rem;
-  }
-
-  .pill {
-    display: flex;
-    align-items: center;
-    --pill-accent: var(--bright-blue);
-    background: color-mix(in srgb, var(--pill-accent) 5%, transparent);
-    color: var(--pill-accent);
-    padding-inline: 0.75rem;
-    padding-block: 0.375rem;
-    border-radius: 2.75rem;
-    border: 0;
-    transition: background 0.3s ease;
-    font-family: var(--inter-font);
-    font-size: 0.875rem;
-    font-style: normal;
-    font-weight: 500;
-    line-height: 1.4rem;
-    letter-spacing: -0.00875rem;
-    text-decoration: none;
-    white-space: nowrap;
-  }
-
-  .pill:hover {
-    background: color-mix(in srgb, var(--pill-accent) 15%, transparent);
-  }
-
-  .pill-group .pill:nth-child(6n + 1) {
-    --pill-accent: var(--bright-blue);
-  }
-  .pill-group .pill:nth-child(6n + 2) {
-    --pill-accent: var(--electric-violet);
-  }
-  .pill-group .pill:nth-child(6n + 3) {
-    --pill-accent: var(--french-violet);
-  }
-
-  .pill-group .pill:nth-child(6n + 4),
-  .pill-group .pill:nth-child(6n + 5),
-  .pill-group .pill:nth-child(6n + 6) {
-    --pill-accent: var(--hot-red);
-  }
-
-  .pill-group svg {
-    margin-inline-start: 0.25rem;
-  }
-
-  .social-links {
-    display: flex;
-    align-items: center;
-    gap: 0.73rem;
-    margin-top: 1.5rem;
-  }
-
-  .social-links path {
-    transition: fill 0.3s ease;
-    fill: var(--gray-400);
-  }
-
-  .social-links a:hover svg path {
-    fill: var(--gray-900);
-  }
-
-  @media screen and (max-width: 650px) {
-    .content {
-      flex-direction: column;
-      width: max-content;
-    }
-
-    .divider {
-      height: 1px;
-      width: 100%;
-      background: var(--red-to-pink-to-purple-horizontal-gradient);
-      margin-block: 1.5rem;
-    }
-  }
-</style>
-
-<main class="main">
-  <div class="content">
-    <div class="left-side">
-      <svg
-        xmlns="http://www.w3.org/2000/svg"
-        viewBox="0 0 982 239"
-        fill="none"
-        class="angular-logo"
-      >
-        <g clip-path="url(#a)">
-          <path
-            fill="url(#b)"
-            d="M388.676 191.625h30.849L363.31 31.828h-35.758l-56.215 159.797h30.848l13.174-39.356h60.061l13.256 39.356Zm-65.461-62.675 21.602-64.311h1.227l21.602 64.311h-44.431Zm126.831-7.527v70.202h-28.23V71.839h27.002v20.374h1.392c2.782-6.71 7.2-12.028 13.255-15.956 6.056-3.927 13.584-5.89 22.503-5.89 8.264 0 15.465 1.8 21.684 5.318 6.137 3.518 10.964 8.673 14.319 15.382 3.437 6.71 5.074 14.81 4.992 24.383v76.175h-28.23v-71.92c0-8.019-2.046-14.237-6.219-18.819-4.173-4.5-9.819-6.791-17.102-6.791-4.91 0-9.328 1.063-13.174 3.272-3.846 2.128-6.792 5.237-9.001 9.328-2.046 4.009-3.191 8.918-3.191 14.728ZM589.233 239c-10.147 0-18.82-1.391-26.103-4.091-7.282-2.7-13.092-6.382-17.511-10.964-4.418-4.582-7.528-9.655-9.164-15.219l25.448-6.136c1.145 2.372 2.782 4.663 4.991 6.954 2.209 2.291 5.155 4.255 8.837 5.81 3.683 1.554 8.428 2.291 14.074 2.291 8.019 0 14.647-1.964 19.884-5.81 5.237-3.845 7.856-10.227 7.856-19.064v-22.665h-1.391c-1.473 2.946-3.601 5.892-6.383 9.001-2.782 3.109-6.464 5.645-10.965 7.691-4.582 2.046-10.228 3.109-17.101 3.109-9.165 0-17.511-2.209-25.039-6.545-7.446-4.337-13.42-10.883-17.757-19.474-4.418-8.673-6.628-19.473-6.628-32.565 0-13.091 2.21-24.301 6.628-33.383 4.419-9.082 10.311-15.955 17.839-20.7 7.528-4.746 15.874-7.037 25.039-7.037 7.037 0 12.846 1.145 17.347 3.518 4.582 2.373 8.182 5.236 10.883 8.51 2.7 3.272 4.746 6.382 6.137 9.327h1.554v-19.8h27.821v121.749c0 10.228-2.454 18.737-7.364 25.447-4.91 6.709-11.538 11.7-20.048 15.055-8.509 3.355-18.165 4.991-28.884 4.991Zm.245-71.266c5.974 0 11.047-1.473 15.302-4.337 4.173-2.945 7.446-7.118 9.573-12.519 2.21-5.482 3.274-12.027 3.274-19.637 0-7.609-1.064-14.155-3.274-19.8-2.127-5.646-5.318-10.064-9.491-13.255-4.174-3.11-9.329-4.746-15.384-4.746s-11.537 1.636-15.792 4.91c-4.173 3.272-7.365 7.772-9.492 13.418-2.128 5.727-3.191 12.191-3.191 19.392 0 7.2 1.063 13.745 3.273 19.228 2.127 5.482 5.318 9.736 9.573 12.764 4.174 3.027 9.41 4.582 15.629 4.582Zm141.56-26.51V71.839h28.23v119.786h-27.412v-21.273h-1.227c-2.7 6.709-7.119 12.191-13.338 16.446-6.137 4.255-13.747 6.382-22.748 6.382-7.855 0-14.81-1.718-20.783-5.237-5.974-3.518-10.72-8.591-14.075-15.382-3.355-6.709-5.073-14.891-5.073-24.464V71.839h28.312v71.921c0 7.609 2.046 13.664 6.219 18.083 4.173 4.5 9.655 6.709 16.365 6.709 4.173 0 8.183-.982 12.111-3.028 3.927-2.045 7.118-5.072 9.655-9.082 2.537-4.091 3.764-9.164 3.764-15.218Zm65.707-109.395v159.796h-28.23V31.828h28.23Zm44.841 162.169c-7.61 0-14.402-1.391-20.457-4.091-6.055-2.7-10.883-6.791-14.32-12.109-3.518-5.319-5.237-11.946-5.237-19.801 0-6.791 1.228-12.355 3.765-16.773 2.536-4.419 5.891-7.937 10.228-10.637 4.337-2.618 9.164-4.664 14.647-6.055 5.4-1.391 11.046-2.373 16.856-3.027 7.037-.737 12.683-1.391 17.102-1.964 4.337-.573 7.528-1.555 9.574-2.782 1.963-1.309 3.027-3.273 3.027-5.973v-.491c0-5.891-1.718-10.391-5.237-13.664-3.518-3.191-8.51-4.828-15.056-4.828-6.955 0-12.356 1.473-16.447 4.5-4.009 3.028-6.71 6.546-8.183 10.719l-26.348-3.764c2.046-7.282 5.483-13.336 10.31-18.328 4.746-4.909 10.638-8.59 17.511-11.045 6.955-2.455 14.565-3.682 22.912-3.682 5.809 0 11.537.654 17.265 2.045s10.965 3.6 15.711 6.71c4.746 3.109 8.51 7.282 11.455 12.6 2.864 5.318 4.337 11.946 4.337 19.883v80.184h-27.166v-16.446h-.9c-1.719 3.355-4.092 6.464-7.201 9.328-3.109 2.864-6.955 5.237-11.619 6.955-4.828 1.718-10.229 2.536-16.529 2.536Zm7.364-20.701c5.646 0 10.556-1.145 14.729-3.354 4.173-2.291 7.364-5.237 9.655-9.001 2.292-3.763 3.355-7.854 3.355-12.273v-14.155c-.9.737-2.373 1.391-4.5 2.046-2.128.654-4.419 1.145-7.037 1.636-2.619.491-5.155.9-7.692 1.227-2.537.328-4.746.655-6.628.901-4.173.572-8.019 1.472-11.292 2.781-3.355 1.31-5.973 3.11-7.855 5.401-1.964 2.291-2.864 5.318-2.864 8.918 0 5.237 1.882 9.164 5.728 11.782 3.682 2.782 8.51 4.091 14.401 4.091Zm64.643 18.328V71.839h27.412v19.965h1.227c2.21-6.955 5.974-12.274 11.292-16.038 5.319-3.763 11.456-5.645 18.329-5.645 1.555 0 3.355.082 5.237.163 1.964.164 3.601.328 4.91.573v25.938c-1.227-.41-3.109-.819-5.646-1.146a58.814 58.814 0 0 0-7.446-.49c-5.155 0-9.738 1.145-13.829 3.354-4.091 2.209-7.282 5.236-9.655 9.164-2.373 3.927-3.519 8.427-3.519 13.5v70.448h-28.312ZM222.077 39.192l-8.019 125.923L137.387 0l84.69 39.192Zm-53.105 162.825-57.933 33.056-57.934-33.056 11.783-28.556h92.301l11.783 28.556ZM111.039 62.675l30.357 73.803H80.681l30.358-73.803ZM7.937 165.115 0 39.192 84.69 0 7.937 165.115Z"
-          />
-          <path
-            fill="url(#c)"
-            d="M388.676 191.625h30.849L363.31 31.828h-35.758l-56.215 159.797h30.848l13.174-39.356h60.061l13.256 39.356Zm-65.461-62.675 21.602-64.311h1.227l21.602 64.311h-44.431Zm126.831-7.527v70.202h-28.23V71.839h27.002v20.374h1.392c2.782-6.71 7.2-12.028 13.255-15.956 6.056-3.927 13.584-5.89 22.503-5.89 8.264 0 15.465 1.8 21.684 5.318 6.137 3.518 10.964 8.673 14.319 15.382 3.437 6.71 5.074 14.81 4.992 24.383v76.175h-28.23v-71.92c0-8.019-2.046-14.237-6.219-18.819-4.173-4.5-9.819-6.791-17.102-6.791-4.91 0-9.328 1.063-13.174 3.272-3.846 2.128-6.792 5.237-9.001 9.328-2.046 4.009-3.191 8.918-3.191 14.728ZM589.233 239c-10.147 0-18.82-1.391-26.103-4.091-7.282-2.7-13.092-6.382-17.511-10.964-4.418-4.582-7.528-9.655-9.164-15.219l25.448-6.136c1.145 2.372 2.782 4.663 4.991 6.954 2.209 2.291 5.155 4.255 8.837 5.81 3.683 1.554 8.428 2.291 14.074 2.291 8.019 0 14.647-1.964 19.884-5.81 5.237-3.845 7.856-10.227 7.856-19.064v-22.665h-1.391c-1.473 2.946-3.601 5.892-6.383 9.001-2.782 3.109-6.464 5.645-10.965 7.691-4.582 2.046-10.228 3.109-17.101 3.109-9.165 0-17.511-2.209-25.039-6.545-7.446-4.337-13.42-10.883-17.757-19.474-4.418-8.673-6.628-19.473-6.628-32.565 0-13.091 2.21-24.301 6.628-33.383 4.419-9.082 10.311-15.955 17.839-20.7 7.528-4.746 15.874-7.037 25.039-7.037 7.037 0 12.846 1.145 17.347 3.518 4.582 2.373 8.182 5.236 10.883 8.51 2.7 3.272 4.746 6.382 6.137 9.327h1.554v-19.8h27.821v121.749c0 10.228-2.454 18.737-7.364 25.447-4.91 6.709-11.538 11.7-20.048 15.055-8.509 3.355-18.165 4.991-28.884 4.991Zm.245-71.266c5.974 0 11.047-1.473 15.302-4.337 4.173-2.945 7.446-7.118 9.573-12.519 2.21-5.482 3.274-12.027 3.274-19.637 0-7.609-1.064-14.155-3.274-19.8-2.127-5.646-5.318-10.064-9.491-13.255-4.174-3.11-9.329-4.746-15.384-4.746s-11.537 1.636-15.792 4.91c-4.173 3.272-7.365 7.772-9.492 13.418-2.128 5.727-3.191 12.191-3.191 19.392 0 7.2 1.063 13.745 3.273 19.228 2.127 5.482 5.318 9.736 9.573 12.764 4.174 3.027 9.41 4.582 15.629 4.582Zm141.56-26.51V71.839h28.23v119.786h-27.412v-21.273h-1.227c-2.7 6.709-7.119 12.191-13.338 16.446-6.137 4.255-13.747 6.382-22.748 6.382-7.855 0-14.81-1.718-20.783-5.237-5.974-3.518-10.72-8.591-14.075-15.382-3.355-6.709-5.073-14.891-5.073-24.464V71.839h28.312v71.921c0 7.609 2.046 13.664 6.219 18.083 4.173 4.5 9.655 6.709 16.365 6.709 4.173 0 8.183-.982 12.111-3.028 3.927-2.045 7.118-5.072 9.655-9.082 2.537-4.091 3.764-9.164 3.764-15.218Zm65.707-109.395v159.796h-28.23V31.828h28.23Zm44.841 162.169c-7.61 0-14.402-1.391-20.457-4.091-6.055-2.7-10.883-6.791-14.32-12.109-3.518-5.319-5.237-11.946-5.237-19.801 0-6.791 1.228-12.355 3.765-16.773 2.536-4.419 5.891-7.937 10.228-10.637 4.337-2.618 9.164-4.664 14.647-6.055 5.4-1.391 11.046-2.373 16.856-3.027 7.037-.737 12.683-1.391 17.102-1.964 4.337-.573 7.528-1.555 9.574-2.782 1.963-1.309 3.027-3.273 3.027-5.973v-.491c0-5.891-1.718-10.391-5.237-13.664-3.518-3.191-8.51-4.828-15.056-4.828-6.955 0-12.356 1.473-16.447 4.5-4.009 3.028-6.71 6.546-8.183 10.719l-26.348-3.764c2.046-7.282 5.483-13.336 10.31-18.328 4.746-4.909 10.638-8.59 17.511-11.045 6.955-2.455 14.565-3.682 22.912-3.682 5.809 0 11.537.654 17.265 2.045s10.965 3.6 15.711 6.71c4.746 3.109 8.51 7.282 11.455 12.6 2.864 5.318 4.337 11.946 4.337 19.883v80.184h-27.166v-16.446h-.9c-1.719 3.355-4.092 6.464-7.201 9.328-3.109 2.864-6.955 5.237-11.619 6.955-4.828 1.718-10.229 2.536-16.529 2.536Zm7.364-20.701c5.646 0 10.556-1.145 14.729-3.354 4.173-2.291 7.364-5.237 9.655-9.001 2.292-3.763 3.355-7.854 3.355-12.273v-14.155c-.9.737-2.373 1.391-4.5 2.046-2.128.654-4.419 1.145-7.037 1.636-2.619.491-5.155.9-7.692 1.227-2.537.328-4.746.655-6.628.901-4.173.572-8.019 1.472-11.292 2.781-3.355 1.31-5.973 3.11-7.855 5.401-1.964 2.291-2.864 5.318-2.864 8.918 0 5.237 1.882 9.164 5.728 11.782 3.682 2.782 8.51 4.091 14.401 4.091Zm64.643 18.328V71.839h27.412v19.965h1.227c2.21-6.955 5.974-12.274 11.292-16.038 5.319-3.763 11.456-5.645 18.329-5.645 1.555 0 3.355.082 5.237.163 1.964.164 3.601.328 4.91.573v25.938c-1.227-.41-3.109-.819-5.646-1.146a58.814 58.814 0 0 0-7.446-.49c-5.155 0-9.738 1.145-13.829 3.354-4.091 2.209-7.282 5.236-9.655 9.164-2.373 3.927-3.519 8.427-3.519 13.5v70.448h-28.312ZM222.077 39.192l-8.019 125.923L137.387 0l84.69 39.192Zm-53.105 162.825-57.933 33.056-57.934-33.056 11.783-28.556h92.301l11.783 28.556ZM111.039 62.675l30.357 73.803H80.681l30.358-73.803ZM7.937 165.115 0 39.192 84.69 0 7.937 165.115Z"
-          />
-        </g>
-        <defs>
-          <radialGradient
-            id="c"
-            cx="0"
-            cy="0"
-            r="1"
-            gradientTransform="rotate(118.122 171.182 60.81) scale(205.794)"
-            gradientUnits="userSpaceOnUse"
-          >
-            <stop stop-color="#FF41F8" />
-            <stop offset=".707" stop-color="#FF41F8" stop-opacity=".5" />
-            <stop offset="1" stop-color="#FF41F8" stop-opacity="0" />
-          </radialGradient>
-          <linearGradient
-            id="b"
-            x1="0"
-            x2="982"
-            y1="192"
-            y2="192"
-            gradientUnits="userSpaceOnUse"
-          >
-            <stop stop-color="#F0060B" />
-            <stop offset="0" stop-color="#F0070C" />
-            <stop offset=".526" stop-color="#CC26D5" />
-            <stop offset="1" stop-color="#7702FF" />
-          </linearGradient>
-          <clipPath id="a"><path fill="#fff" d="M0 0h982v239H0z" /></clipPath>
-        </defs>
-      </svg>
-      <h1>Hello, {{ title() }}</h1>
-      <p>Congratulations! Your app is running. 🎉</p>
-    </div>
-    <div class="divider" role="separator" aria-label="Divider"></div>
-    <div class="right-side">
-      <div class="pill-group">
-        @for (item of [
-          { title: 'Explore the Docs', link: 'https://angular.dev' },
-          { title: 'Learn with Tutorials', link: 'https://angular.dev/tutorials' },
-          { title: 'Prompt and best practices for AI', link: 'https://angular.dev/ai/develop-with-ai'},
-          { title: 'CLI Docs', link: 'https://angular.dev/tools/cli' },
-          { title: 'Angular Language Service', link: 'https://angular.dev/tools/language-service' },
-          { title: 'Angular DevTools', link: 'https://angular.dev/tools/devtools' },
-        ]; track item.title) {
-          <a
-            class="pill"
-            [href]="item.link"
-            target="_blank"
-            rel="noopener"
-          >
-            <span>{{ item.title }}</span>
-            <svg
-              xmlns="http://www.w3.org/2000/svg"
-              height="14"
-              viewBox="0 -960 960 960"
-              width="14"
-              fill="currentColor"
-            >
-              <path
-                d="M200-120q-33 0-56.5-23.5T120-200v-560q0-33 23.5-56.5T200-840h280v80H200v560h560v-280h80v280q0 33-23.5 56.5T760-120H200Zm188-212-56-56 372-372H560v-80h280v280h-80v-144L388-332Z"
-              />
-            </svg>
-          </a>
-        }
-      </div>
-      <div class="social-links">
-        <a
-          href="https://github.com/angular/angular"
-          aria-label="Github"
-          target="_blank"
-          rel="noopener"
-        >
-          <svg
-            width="25"
-            height="24"
-            viewBox="0 0 25 24"
-            fill="none"
-            xmlns="http://www.w3.org/2000/svg"
-            alt="Github"
-          >
-            <path
-              d="M12.3047 0C5.50634 0 0 5.50942 0 12.3047C0 17.7423 3.52529 22.3535 8.41332 23.9787C9.02856 24.0946 9.25414 23.7142 9.25414 23.3871C9.25414 23.0949 9.24389 22.3207 9.23876 21.2953C5.81601 22.0377 5.09414 19.6444 5.09414 19.6444C4.53427 18.2243 3.72524 17.8449 3.72524 17.8449C2.61064 17.082 3.81137 17.0973 3.81137 17.0973C5.04697 17.1835 5.69604 18.3647 5.69604 18.3647C6.79321 20.2463 8.57636 19.7029 9.27978 19.3881C9.39052 18.5924 9.70736 18.0499 10.0591 17.7423C7.32641 17.4347 4.45429 16.3765 4.45429 11.6618C4.45429 10.3185 4.9311 9.22133 5.72065 8.36C5.58222 8.04931 5.16694 6.79833 5.82831 5.10337C5.82831 5.10337 6.85883 4.77319 9.2121 6.36459C10.1965 6.09082 11.2424 5.95546 12.2883 5.94931C13.3342 5.95546 14.3801 6.09082 15.3644 6.36459C17.7023 4.77319 18.7328 5.10337 18.7328 5.10337C19.3942 6.79833 18.9789 8.04931 18.8559 8.36C19.6403 9.22133 20.1171 10.3185 20.1171 11.6618C20.1171 16.3888 17.2409 17.4296 14.5031 17.7321C14.9338 18.1012 15.3337 18.8559 15.3337 20.0084C15.3337 21.6552 15.3183 22.978 15.3183 23.3779C15.3183 23.7009 15.5336 24.0854 16.1642 23.9623C21.0871 22.3484 24.6094 17.7341 24.6094 12.3047C24.6094 5.50942 19.0999 0 12.3047 0Z"
-            />
-          </svg>
-        </a>
-        <a
-          href="https://x.com/angular"
-          aria-label="X"
-          target="_blank"
-          rel="noopener"
-        >
-          <svg
-            width="24"
-            height="24"
-            viewBox="0 0 24 24"
-            fill="none"
-            xmlns="http://www.w3.org/2000/svg"
-            alt="X"
-          >
-            <path
-              d="M18.244 2.25h3.308l-7.227 8.26 8.502 11.24H16.17l-5.214-6.817L4.99 21.75H1.68l7.73-8.835L1.254 2.25H8.08l4.713 6.231zm-1.161 17.52h1.833L7.084 4.126H5.117z"
-            />
-          </svg>
-        </a>
-        <a
-          href="https://www.youtube.com/channel/UCbn1OgGei-DV7aSRo_HaAiw"
-          aria-label="Youtube"
-          target="_blank"
-          rel="noopener"
-        >
-          <svg
-            width="29"
-            height="20"
-            viewBox="0 0 29 20"
-            fill="none"
-            xmlns="http://www.w3.org/2000/svg"
-            alt="Youtube"
-          >
-            <path
-              fill-rule="evenodd"
-              clip-rule="evenodd"
-              d="M27.4896 1.52422C27.9301 1.96749 28.2463 2.51866 28.4068 3.12258C29.0004 5.35161 29.0004 10 29.0004 10C29.0004 10 29.0004 14.6484 28.4068 16.8774C28.2463 17.4813 27.9301 18.0325 27.4896 18.4758C27.0492 18.9191 26.5 19.2389 25.8972 19.4032C23.6778 20 14.8068 20 14.8068 20C14.8068 20 5.93586 20 3.71651 19.4032C3.11363 19.2389 2.56449 18.9191 2.12405 18.4758C1.68361 18.0325 1.36732 17.4813 1.20683 16.8774C0.613281 14.6484 0.613281 10 0.613281 10C0.613281 10 0.613281 5.35161 1.20683 3.12258C1.36732 2.51866 1.68361 1.96749 2.12405 1.52422C2.56449 1.08095 3.11363 0.76113 3.71651 0.596774C5.93586 0 14.8068 0 14.8068 0C14.8068 0 23.6778 0 25.8972 0.596774C26.5 0.76113 27.0492 1.08095 27.4896 1.52422ZM19.3229 10L11.9036 5.77905V14.221L19.3229 10Z"
-            />
-          </svg>
-        </a>
-      </div>
-    </div>
-  </div>
-</main>
-
-<!-- * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * -->
-<!-- * * * * * * * * * * * The content above * * * * * * * * * * * * -->
-<!-- * * * * * * * * * * is only a placeholder * * * * * * * * * * * -->
-<!-- * * * * * * * * * * and can be replaced.  * * * * * * * * * * * -->
-<!-- * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * -->
-<!-- * * * * * * * * * * End of Placeholder  * * * * * * * * * * * * -->
-<!-- * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * -->
-
-
-<router-outlet />
+<router-outlet />
--- a/frontend/src/app/app.ts
+++ b/frontend/src/app/app.ts
@@ -5,7 +5,7 @@ import { RouterOutlet } from '@angular/router';
  selector: 'app-root',
  standalone: true,
  imports: [RouterOutlet],
-  template: `<router-outlet />`,
+  template: '<router-outlet />',
  styles: [`
    :host {
      display: block;
--- a/frontend/src/app/command-hub/components/agent-card/agent-card.component.html
+++ b/frontend/src/app/command-hub/components/agent-card/agent-card.component.html
@@ -2,11 +2,13 @@
 <!-- AgentCard — per spec Section 7.3                                            -->
 <!-- Integrates: Status Badge · Task Progress Bar · Quick‑Jump Button           -->
 <!-- Left‑border accent matches status color. role="article" + aria‑labels.     -->
+<!-- Enhanced: data-status attribute, elapsed time, design tokens.              -->
 <!-- ========================================================================== -->
 <article
  class="agent-card"
  role="article"
-  [attr.aria-label]="displayName + ' — ' + statusLabel()"
+  [attr.data-status]="status"
+  [attr.aria-label]="(displayName || agentId) + ' — ' + statusLabel()"
  [style.border-left-color]="statusBorderColor()"
  (click)="cardClick.emit(sessionKey)"
  appLongPress
@@ -32,19 +34,20 @@
  </div>

  <!-- ── Body: current task ── -->
-  <div class="agent-card__body" *ngIf="task || status === 'error'">
+  <div class="agent-card__body" *ngIf="task || isError()">
    <p
      class="agent-card__task"
-      [attr.aria-label]="'Current task: ' + (status === 'error' ? errorMessage : task)"
+      [class.agent-card__task--error]="isError()"
+      [attr.aria-label]="'Current task: ' + (isError() ? errorMessage || task : task)"
    >
-      {{ status === 'error' ? errorMessage || task : task }}
+      {{ isError() ? errorMessage || task : task }}
    </p>
  </div>

  <!-- ── Task Progress Bar ── -->
  <div
    class="agent-card__progress"
-    *ngIf="progress > 0 && status !== 'error'"
+    *ngIf="showProgress()"
    [attr.aria-label]="'Task progress: ' + progress + '%'"
  >
    <mat-progress-bar
@@ -55,6 +58,16 @@
    <span class="agent-card__progress-label text-mono">{{ progress }}%</span>
  </div>

+  <!-- ── Elapsed Time ── -->
+  <div
+    class="agent-card__elapsed"
+    *ngIf="taskElapsed && isActiveLike()"
+    [attr.aria-label]="'Elapsed: ' + taskElapsed"
+  >
+    <mat-icon aria-hidden="true" class="agent-card__elapsed-icon">schedule</mat-icon>
+    <span class="text-mono">{{ taskElapsed }}</span>
+  </div>
+
  <!-- ── Footer: channel + last activity + quick‑jump ── -->
  <div class="agent-card__footer">
    <div class="agent-card__meta">
--- a/frontend/src/app/command-hub/components/agent-card/agent-card.component.scss
+++ b/frontend/src/app/command-hub/components/agent-card/agent-card.component.scss
@@ -2,15 +2,18 @@
 // AgentCard — M3 tactical dark styling
 // Per spec Section 7.3: left‑border accent, status‑aware coloring,
 // responsive card layout with 320px min‑width.
+// Enhanced: data-status selectors, elapsed time, design token imports.
 // ============================================================================

+@use 'tokens' as tokens;
+
 .agent-card {
  display: flex;
  flex-direction: column;
-  min-width: var(--cc-card-min-width);
-  padding: var(--cc-card-padding);
+  min-width: tokens.$cc-card-min-width;
+  padding: tokens.$cc-card-padding;
  background-color: var(--cc-surface-container);
-  border-radius: var(--cc-card-border-radius);
+  border-radius: tokens.$cc-card-border-radius;
  border-left: 4px solid var(--status-offline); // default; overridden by [style]
  border-top: 1px solid var(--cc-outline);
  border-right: 1px solid var(--cc-outline);
@@ -56,11 +59,6 @@
  letter-spacing: 0.02em;
  text-transform: uppercase;
  color: var(--cc-on-surface);
-
-  // Per‑status background tints
-  .status-dot--active + & {
-    background-color: var(--status-active-bg);
-  }
 }

 .agent-card__status-label {
@@ -102,8 +100,7 @@
  color: var(--cc-on-surface);
  line-height: 1.4;

-  // Error messages get distinct styling
-  .agent-card--error & {
+  &--error {
    color: var(--status-error);
  }
 }
@@ -117,6 +114,7 @@
 }

 .agent-card__progress-label {
+  font-family: var(--cc-font-mono);
  font-size: 12px;
  font-weight: 500;
  color: var(--cc-on-surface-variant);
@@ -138,6 +136,23 @@
  }
 }

+// ── Elapsed Time ──
+.agent-card__elapsed {
+  display: flex;
+  align-items: center;
+  gap: 4px;
+  font-size: 12px;
+  color: var(--cc-on-surface-variant);
+  padding: 2px 0;
+}
+
+.agent-card__elapsed-icon {
+  font-size: 14px;
+  width: 14px;
+  height: 14px;
+  color: var(--status-thinking);
+}
+
 // ── Footer ──
 .agent-card__footer {
  display: flex;
@@ -161,7 +176,6 @@
  color: var(--cc-on-surface-variant);
 }

-.agent-card__channel-icon,
 .agent-card__channel .mat-icon {
  font-size: 14px;
  width: 14px;
@@ -177,7 +191,6 @@
 .agent-card__jump {
  flex-shrink: 0;

-  // Match M3 text button sizing
  .mat-mdc-button {
    min-width: 36px;
    padding: 0 8px;
@@ -192,11 +205,9 @@
 }

 // ── Status‑specific background tints for badge ──
-// We use the global status-dot classes from styles.scss and pair them
-// with contextual background-color overrides here.
+// Using data-status attribute selectors for clean styling.

-.agent-card[data-status="active"] .agent-card__badge,
-.agent-card .status-dot--active ~ .agent-card__badge {
+.agent-card[data-status="active"] .agent-card__badge {
  background-color: var(--status-active-bg);
 }

@@ -212,8 +223,22 @@
  background-color: var(--status-error-bg);
 }

+.agent-card[data-status="offline"] .agent-card__badge {
+  background-color: var(--cc-surface-container-high);
+}
+
+// ── Active‑like pulse on card border ──
+.agent-card[data-status="active"],
+.agent-card[data-status="thinking"] {
+  border-left-width: 4px;
+}
+
+.agent-card[data-status="error"] {
+  border-left-color: var(--status-error);
+}
+
 // ── Responsive ──
-@media (max-width: 599px) {
+@media (max-width: tokens.$cc-breakpoint-mobile) {
  .agent-card {
    min-width: unset;
    padding: 16px;
--- a/frontend/src/app/command-hub/components/agent-card/agent-card.component.ts
+++ b/frontend/src/app/command-hub/components/agent-card/agent-card.component.ts
@@ -3,8 +3,12 @@ import {
  Component,
  EventEmitter,
  Input,
+  OnDestroy,
  Output,
  computed,
+  effect,
+  inject,
+  signal,
 } from '@angular/core';
 import { CommonModule } from '@angular/common';
 import { RouterModule } from '@angular/router';
@@ -14,12 +18,18 @@ import { MatProgressBarModule } from '@angular/material/progress-bar';
 import { MatTooltipModule } from '@angular/material/tooltip';
 import { AgentStatus } from '../../../models/agent.model';
 import { LongPressDirective } from '../../../directives/long-press.directive';
+import {
+  STATUS_COLORS,
+  STATUS_LABELS,
+  CHANNEL_ICONS,
+} from '../../../design/tokens';

 // ============================================================================
 // AgentCard Component
 // Per spec Section 7.3: Composes Agent Status Badge, Task Progress Bar,
 // and Quick‑Jump Button into a card with left‑border status accent.
 // CUB-26: Emits cardClick and cardLongPress for drawer/modal integration.
+// Enhanced with data-status attribute, elapsed time, and design tokens.
 // ============================================================================

@Component({
@@ -38,7 +48,7 @@ import { LongPressDirective } from '../../../directives/long-press.directive';
  styleUrl: './agent-card.component.scss',
  changeDetection: ChangeDetectionStrategy.OnPush,
 })
-export class AgentCardComponent {
+export class AgentCardComponent implements OnDestroy {
  // --- Six required inputs per spec ---

  /** Agent status — drives badge color and left‑border accent */
@@ -73,6 +83,9 @@ export class AgentCardComponent {
  /** Error message (shown only when status is 'error') */
  @Input() errorMessage = '';

+  /** Elapsed time string, e.g. "04m 12s" */
+  @Input() taskElapsed = '';
+
  // --- CUB-26: Outputs for drawer/modal integration ---

  /** Emitted when the card is clicked — opens the session drawer. */
@@ -81,7 +94,15 @@ export class AgentCardComponent {
  /** Emitted when the card is long-pressed — bypasses drawer, opens session log directly. */
  @Output() readonly cardLongPress = new EventEmitter<string>();

-  // --- Computed values ---
+  // --- Internal state ---
+
+  /** Timer for refreshing relative-time label */
+  private _timer: ReturnType<typeof setInterval> | null = null;
+
+  /** Internal signal to trigger relative-time recomputation */
+  private readonly _tick = signal(0);
+
+  // --- Computed values using design tokens ---

  /** Map status → CSS custom property for the left‑border accent */
  readonly statusBorderColor = computed(() => {
@@ -95,46 +116,68 @@ export class AgentCardComponent {
    return map[this.status] ?? 'var(--status-offline)';
  });

-  /** Human‑readable status label */
-  readonly statusLabel = computed(() => {
-    const labels: Record<AgentStatus, string> = {
-      active: 'Active',
-      idle: 'Idle',
-      thinking: 'Thinking…',
-      error: 'Error',
-      offline: 'Offline',
-    };
-    return labels[this.status] ?? this.status;
-  });
+  /** Human‑readable status label (from design tokens) */
+  readonly statusLabel = computed(() => STATUS_LABELS[this.status] ?? this.status);

  /** CSS class suffix for the status badge dot */
  readonly statusDotClass = computed(() => `status-dot--${this.status}`);

-  /** Material icon name for the channel */
-  readonly channelIcon = computed(() => {
-    const icons: Record<string, string> = {
-      telegram: 'telegram',  // falls back to font icon if no SVG registered
-      slack: 'chat',
-      discord: 'forum',
-      whatsapp: 'chat',
-      webchat: 'language',
-      email: 'email',
-    };
-    return icons[this.channel] ?? 'chat';
+  /** Material icon name for the channel (from design tokens) */
+  readonly channelIcon = computed(() => CHANNEL_ICONS[this.channel] ?? 'chat');
+
+  /** Relative time string for lastActivity, refreshed every 30s */
+  readonly lastActivityLabel = computed(() => {
+    // Read tick to create dependency that forces recomputation
+    this._tick();
+    return this._relativeTime(this.lastActivity);
  });

-  /** Relative time string for lastActivity */
-  readonly lastActivityLabel = computed(() => {
-    if (!this.lastActivity) return '';
+  /** Quick‑jump route derived from sessionKey */
+  readonly jumpRoute = computed(() => `/sessions/${this.sessionKey}`);
+
+  /** Whether progress bar should show */
+  readonly showProgress = computed(() => this.progress > 0 && this.status !== 'error');
+
+  /** Whether error state is active */
+  readonly isError = computed(() => this.status === 'error');
+
+  /** Whether card is in an active-like state (active or thinking) */
+  readonly isActiveLike = computed(() => this.status === 'active' || this.status === 'thinking');
+
+  constructor() {
+    // Start the relative-time refresh timer
+    this._startTimer();
+  }
+
+  ngOnDestroy(): void {
+    this._stopTimer();
+  }
+
+  // --- Private helpers ---
+
+  private _relativeTime(date: Date | null | undefined): string {
+    if (!date) return '';
    const now = Date.now();
-    const then = this.lastActivity.getTime();
+    const then = date.getTime();
    const diffSec = Math.max(0, Math.floor((now - then) / 1000));
    if (diffSec < 60) return 'just now';
    if (diffSec < 3600) return `${Math.floor(diffSec / 60)}m ago`;
    if (diffSec < 86400) return `${Math.floor(diffSec / 3600)}h ago`;
    return `${Math.floor(diffSec / 86400)}d ago`;
-  });
+  }

-  /** Quick‑jump route derived from sessionKey */
-  readonly jumpRoute = computed(() => `/sessions/${this.sessionKey}`);
+  private _startTimer(): void {
+    this._stopTimer();
+    this._timer = setInterval(() => {
+      // Increment tick to force lastActivityLabel recomputation
+      this._tick.update(v => v + 1);
+    }, 30_000);
+  }
+
+  private _stopTimer(): void {
+    if (this._timer) {
+      clearInterval(this._timer);
+      this._timer = null;
+    }
+  }
 }
--- a/frontend/src/app/components/adaptive-navigation/adaptive-navigation.component.scss
+++ b/frontend/src/app/components/adaptive-navigation/adaptive-navigation.component.scss
@@ -1,14 +1,16 @@
 // ============================================================================
 // Adaptive Navigation — Desktop sidebar / Mobile header
-// Desktop (≥768px): 72px sidebar with full navigation items
-// Mobile (<768px):  56px compact header with hamburger menu
+// Per CUB-27 spec breakpoints:
+//   Compact  (0–599px):  Mobile header + hamburger + drawer
+//   Medium   (600–1023px): Collapsed sidebar (icon-only, 72px)
+//   Expanded (≥1024px):  Full sidebar with labels (72px collapsed, 256px expanded)
 // ============================================================================

 // ---------------------------------------------------------------------------
-// Desktop Sidebar (visible ≥768px)
+// Desktop Sidebar (visible ≥600px)
 // ---------------------------------------------------------------------------
 .adaptive-nav__sidebar {
-  display: flex;
+  display: none; // Hidden by default (mobile-first)
  flex-direction: column;
  width: var(--cc-nav-rail-collapsed-width, 72px);
  min-height: 100vh;
@@ -152,12 +154,12 @@
 }

 // ---------------------------------------------------------------------------
-// Mobile Header (visible <768px)
+// Mobile Header (visible <600px only)
 // ---------------------------------------------------------------------------
 .adaptive-nav__mobile-header {
  display: none; // Hidden on desktop, shown on mobile via media query
  align-items: center;
-  height: 56px;
+  height: var(--cc-header-height-compact, 56px);
  padding: 0 12px;
  background-color: var(--cc-surface-container-high);
  border-bottom: 1px solid var(--cc-outline);
@@ -167,6 +169,8 @@

 .adaptive-nav__hamburger {
  color: var(--cc-on-surface-variant) !important;
+  min-width: 48px;
+  min-height: 48px;

  &:hover {
    color: var(--cc-on-surface) !important;
@@ -196,6 +200,8 @@

 .adaptive-nav__mobile-action {
  color: var(--cc-on-surface-variant) !important;
+  min-width: 48px;
+  min-height: 48px;

  &:hover {
    color: var(--cc-on-surface) !important;
@@ -214,7 +220,7 @@

 .adaptive-nav__mobile-drawer {
  position: fixed;
-  top: 56px; // Below header
+  top: var(--cc-header-height-compact, 56px); // Below header
  left: 0;
  bottom: 0;
  width: 280px;
@@ -271,34 +277,73 @@
 }

 // ---------------------------------------------------------------------------
-// Media Queries — Layout Switch
+// Media Queries — Layout Switch (CUB-27 breakpoints)
 // ---------------------------------------------------------------------------
-// Desktop (≥768px): Show sidebar, hide mobile header
-// Mobile (<768px):  Hide sidebar, show compact header
-// ---------------------------------------------------------------------------
-@media (min-width: 768px) {
+
+// Compact (0–599px): Show mobile header, hide sidebar
+@media (max-width: 599px) {
+  .adaptive-nav__sidebar {
+    display: none;
+  }
+
+  .adaptive-nav__mobile-header {
+    display: flex;
+  }
+
+  // Hide mobile drawer and overlay on desktop
+  .adaptive-nav__overlay,
+  .adaptive-nav__mobile-drawer {
+    // These are conditional via @if in template, no display:none needed
+  }
+}
+
+// Medium (600–1023px): Show collapsed sidebar (icon-only), hide mobile
+@media (min-width: 600px) and (max-width: 1023px) {
  .adaptive-nav__sidebar {
    display: flex;
+    width: var(--cc-nav-rail-collapsed-width, 72px);
+  }
+
+  // Hide labels on medium (collapsed)
+  .adaptive-nav__sidebar-label,
+  .adaptive-nav__brand {
+    display: none;
+  }
+
+  .adaptive-nav__sidebar-header {
+    justify-content: center;
+  }
+
+  .adaptive-nav__sidebar-item {
+    flex-direction: column;
+    justify-content: center;
  }

  .adaptive-nav__mobile-header {
    display: none;
  }

-  // Hide mobile drawer and overlay on desktop
  .adaptive-nav__overlay,
  .adaptive-nav__mobile-drawer {
    display: none;
  }
 }

-@media (max-width: 767px) {
+// Expanded (≥1024px): Show sidebar with labels
+@media (min-width: 1024px) {
  .adaptive-nav__sidebar {
-    display: none;
+    display: flex;
+    width: var(--cc-nav-rail-collapsed-width, 72px);
+    transition: width 200ms cubic-bezier(0.4, 0, 0.2, 1);
  }

  .adaptive-nav__mobile-header {
-    display: flex;
+    display: none;
+  }
+
+  .adaptive-nav__overlay,
+  .adaptive-nav__mobile-drawer {
+    display: none;
  }
 }

@@ -313,4 +358,8 @@
  .adaptive-nav__mobile-drawer {
    animation: none;
  }
+
+  .adaptive-nav__sidebar {
+    transition: none;
+  }
 }
--- a/frontend/src/app/components/adaptive-navigation/adaptive-navigation.component.ts
+++ b/frontend/src/app/components/adaptive-navigation/adaptive-navigation.component.ts
@@ -1,4 +1,4 @@
-import { ChangeDetectionStrategy, Component, signal } from '@angular/core';
+import { ChangeDetectionStrategy, Component, signal, HostListener, OnDestroy, OnInit } from '@angular/core';
 import { RouterLink, RouterLinkActive } from '@angular/router';
 import { MatIconModule } from '@angular/material/icon';
 import { MatButtonModule } from '@angular/material/button';
@@ -8,13 +8,14 @@ import { NAV_DESTINATIONS } from '../../models/nav.model';

 /**
 * Adaptive Navigation Component — switches between desktop sidebar
- * and mobile header layouts using CSS media queries.
+ * and mobile header layouts using CSS media queries + JS breakpoint sync.
 *
- * Desktop (≥768px): 72px sidebar with full navigation items.
- * Mobile (<768px):  56px compact header with hamburger menu.
+ * Per CUB-27 spec breakpoints:
+ *   Compact  (0–599px):  Mobile header + hamburger + bottom nav
+ *   Medium   (600–1023px): Collapsed sidebar (icon-only)
+ *   Expanded (≥1024px):  Expandable sidebar (hover/click)
 *
- * The LIVE status indicator is visible in both layouts.
- * Per spec Section 3.1 (kiosk) and 3.2 (mobile).
+ * The LIVE status indicator is visible in all layouts.
 */
@Component({
  selector: 'app-adaptive-navigation',
@@ -31,7 +32,7 @@ import { NAV_DESTINATIONS } from '../../models/nav.model';
  styleUrl: './adaptive-navigation.component.scss',
  changeDetection: ChangeDetectionStrategy.OnPush,
 })
-export class AdaptiveNavigationComponent {
+export class AdaptiveNavigationComponent implements OnInit, OnDestroy {
  /** Navigation destinations shared with other nav components */
  protected readonly destinations = NAV_DESTINATIONS;

@@ -41,6 +42,22 @@ export class AdaptiveNavigationComponent {
  /** Live connection status */
  protected readonly isConnected = signal(true);

+  /** Responsive breakpoint state */
+  protected readonly isMedium = signal(false);
+  protected readonly isExpanded = signal(false);
+
+  private readonly COMPACT_MAX = 599;
+  private readonly MEDIUM_MAX = 1023;
+
+  ngOnInit(): void {
+    this.updateBreakpoint();
+  }
+
+  @HostListener('window:resize')
+  onResize(): void {
+    this.updateBreakpoint();
+  }
+
  /** Toggle mobile menu */
  toggleMobileMenu(): void {
    this.mobileMenuOpen.update((v) => !v);
@@ -50,4 +67,18 @@ export class AdaptiveNavigationComponent {
  closeMobileMenu(): void {
    this.mobileMenuOpen.set(false);
  }
+
+  private updateBreakpoint(): void {
+    const w = window.innerWidth;
+    this.isMedium.set(w >= this.COMPACT_MAX + 1 && w <= this.MEDIUM_MAX);
+    this.isExpanded.set(w > this.MEDIUM_MAX);
+    // Close mobile menu when switching to desktop
+    if (w > this.COMPACT_MAX) {
+      this.mobileMenuOpen.set(false);
+    }
+  }
+
+  ngOnDestroy(): void {
+    // HostListener auto-unsubscribes
+  }
 }
--- a/frontend/src/app/design/tokens.ts
+++ b/frontend/src/app/design/tokens.ts
@@ -94,6 +94,92 @@ export const CcStatusColors = {
  offline:  { fg: '#64748b', bg: 'rgba(100, 116, 139, 0.12)', border: 'rgba(100, 116, 139, 0.40)' },
 } as const;

+// ---------------------------------------------------------------------------
+// Convenience exports for component usage (CUB-20)
+// ---------------------------------------------------------------------------
+/** Status colors — maps AgentStatus to hex values */
+export const STATUS_COLORS: Record<string, string> = {
+  active: '#38BDF8',
+  idle: '#2DD4BF',
+  thinking: '#A78BFA',
+  error: '#F87171',
+  offline: '#64748B',
+};
+
+/** Status background tints (12% opacity) */
+export const STATUS_BG_COLORS: Record<string, string> = {
+  active: 'rgba(56, 189, 248, 0.12)',
+  idle: 'rgba(45, 212, 191, 0.12)',
+  thinking: 'rgba(167, 139, 250, 0.12)',
+  error: 'rgba(248, 113, 113, 0.12)',
+  offline: 'rgba(100, 116, 139, 0.12)',
+};
+
+/** Surface overrides (CUB-20 convenience) */
+export const SURFACE = {
+  background: '#0D0F12',
+  surface: '#13161A',
+  container: '#1C2027',
+  containerHigh: '#252B33',
+  onSurface: '#E2E8F0',
+  onSurfaceVariant: '#8A9BB0',
+  outline: '#2D3748',
+} as const;
+
+/** Tactical Dark Mode color palette (CUB-20 convenience) */
+export const COLORS = {
+  surface: '#0F172A',
+  surfaceLight: '#1E293B',
+  primary: '#38BDF8',
+  secondary: '#2DD4BF',
+  accent: '#A78BFA',
+  danger: '#F87171',
+  textPrimary: '#FFFFFF',
+  textSecondary: '#94A3B8',
+  border: '#334155',
+} as const;
+
+/** Layout constants (CUB-20 convenience) */
+export const LAYOUT = {
+  navRailCollapsedWidth: 72,
+  navRailExpandedWidth: 256,
+  headerHeight: 64,
+  bottomNavHeight: 80,
+  cardBorderRadius: 16,
+  cardMinWidth: 320,
+  cardGap: 16,
+  cardPadding: 20,
+  sectionPadding: 24,
+  spacingUnit: 8,
+} as const;
+
+/** Breakpoints (px) (CUB-20 convenience) */
+export const BREAKPOINTS = {
+  mobile: 599,
+  tablet: 1023,
+  desktop: 1024,
+} as const;
+
+/** Channel icon mapping (CUB-20) */
+export const CHANNEL_ICONS: Record<string, string> = {
+  telegram: 'telegram',
+  slack: 'chat',
+  discord: 'forum',
+  whatsapp: 'chat',
+  webchat: 'language',
+  email: 'email',
+  mqtt: 'sensors',
+};
+
+/** Human-readable status labels (CUB-20) */
+export const STATUS_LABELS: Record<string, string> = {
+  active: 'Active',
+  idle: 'Idle',
+  thinking: 'Thinking…',
+  error: 'Error',
+  offline: 'Offline',
+};
+
 // ---------------------------------------------------------------------------
 // Typography
 // ---------------------------------------------------------------------------
@@ -263,9 +349,6 @@ export const CcTokens = {
 // ---------------------------------------------------------------------------
 // CSS Custom Property Names
 // ---------------------------------------------------------------------------
-// Use these constants when setting styles programmatically via Renderer2
-// or ElementRef.style, e.g.: el.style.setProperty(CcCssProps.colorPrimary, '#fff')
-// ---------------------------------------------------------------------------
 export const CcCssProps = {
  // Color
  colorPrimary:      '--cc-color-primary',
--- a/frontend/src/app/layout/bottom-nav/bottom-nav.component.scss
+++ b/frontend/src/app/layout/bottom-nav/bottom-nav.component.scss
@@ -1,7 +1,8 @@
 // ============================================================================
 // Bottom Navigation Bar — Mobile Navigation
-// Per spec Section 3.2: M3 NavigationBar pattern
-// Visible only on compact breakpoint (< 600px)
+// Per CUB-27 spec breakpoints:
+//   Compact (0–599px): Visible — M3 NavigationBar pattern
+//   Medium+ (≥600px): Hidden — nav rail takes over
 // ============================================================================

 .bottom-nav {
@@ -17,6 +18,8 @@
  align-items: center;
  justify-content: space-around;
  padding: 0 8px;
+  // Safe area inset for notched devices
+  padding-bottom: env(safe-area-inset-bottom, 0px);
 }

 .bottom-nav__item {
@@ -68,9 +71,24 @@
  white-space: nowrap;
 }

-// Show bottom nav only on compact breakpoint
+// ---------------------------------------------------------------------------
+// Compact (0–599px): Show bottom nav
+// ---------------------------------------------------------------------------
@media (max-width: 599px) {
  .bottom-nav {
    display: flex;
  }
+}
+
+// ---------------------------------------------------------------------------
+// Medium+ (≥600px): Hidden — nav rail takes over
+// ---------------------------------------------------------------------------
+
+// ---------------------------------------------------------------------------
+// Accessibility: Reduced Motion
+// ---------------------------------------------------------------------------
+@media (prefers-reduced-motion: reduce) {
+  .bottom-nav__item {
+    transition: none;
+  }
 }
--- a/frontend/src/app/layout/header-bar/header-bar.component.scss
+++ b/frontend/src/app/layout/header-bar/header-bar.component.scss
@@ -1,36 +1,43 @@
 // ============================================================================
 // Header Bar — Top App Bar
-// Per spec Section 3.1: 64px tall, M3 MediumTopAppBar on expanded
-// Section 3.2: SmallTopAppBar on mobile
+// Per CUB-27 spec breakpoints:
+//   Compact  (0–599px):  SmallTopAppBar — 56px height, compact title, hidden labels
+//   Medium   (600–1023px): Medium top bar — 64px height
+//   Expanded (≥1024px):  MediumTopAppBar — 64px height, full actions
 // ============================================================================

 .header-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
-  height: var(--cc-header-height);
-  padding: 0 var(--cc-section-padding);
+  height: var(--cc-header-height-compact); // Compact by default (mobile-first)
+  padding: 0 var(--cc-section-padding-compact);
  background-color: var(--cc-surface-container-high);
  border-bottom: 1px solid var(--cc-outline);
  z-index: 20;
 }

 .header-bar__title {
-  font-size: 28px;
-  font-weight: 400;
+  font-size: 20px;
+  font-weight: 500;
  color: var(--cc-on-surface);
  margin: 0;
  letter-spacing: -0.01em;
+  white-space: nowrap;
+  overflow: hidden;
+  text-overflow: ellipsis;
 }

 .header-bar__actions {
  display: flex;
  align-items: center;
-  gap: 8px;
+  gap: 4px;
 }

 .header-bar__action-btn {
  color: var(--cc-on-surface-variant) !important;
+  min-width: 48px;
+  min-height: 48px;

  &:hover {
    color: var(--cc-on-surface) !important;
@@ -59,18 +66,61 @@
  vertical-align: middle;
 }

-// Mobile: smaller title
+// ---------------------------------------------------------------------------
+// Compact (0–599px): SmallTopAppBar — hide live label, tighter spacing
+// ---------------------------------------------------------------------------
@media (max-width: 599px) {
+  .header-bar__live-label {
+    display: none; // Space saving on compact — dot alone is enough
+  }
+
+  .header-bar__actions {
+    gap: 0;
+  }
+}
+
+// ---------------------------------------------------------------------------
+// Medium (600–1023px): Medium top bar
+// ---------------------------------------------------------------------------
+@media (min-width: 600px) and (max-width: 1023px) {
  .header-bar {
-    padding: 0 16px;
+    height: var(--cc-header-height);
+    padding: 0 var(--cc-section-padding);
  }

  .header-bar__title {
-    font-size: 22px;
-    font-weight: 500;
+    font-size: 24px;
  }

-  .header-bar__live-label {
-    display: none; // Space saving on mobile — dot alone is enough
+  .header-bar__actions {
+    gap: 4px;
+  }
+}
+
+// ---------------------------------------------------------------------------
+// Expanded (≥1024px): Full top bar
+// ---------------------------------------------------------------------------
+@media (min-width: 1024px) {
+  .header-bar {
+    height: var(--cc-header-height);
+    padding: 0 var(--cc-section-padding);
+  }
+
+  .header-bar__title {
+    font-size: 28px;
+    font-weight: 400;
+  }
+
+  .header-bar__actions {
+    gap: 8px;
+  }
+}
+
+// ---------------------------------------------------------------------------
+// Accessibility: Reduced Motion
+// ---------------------------------------------------------------------------
+@media (prefers-reduced-motion: reduce) {
+  .header-bar__live-dot--connected {
+    animation: none;
  }
 }
--- a/frontend/src/app/layout/layout-shell/layout-shell.component.scss
+++ b/frontend/src/app/layout/layout-shell/layout-shell.component.scss
@@ -1,7 +1,9 @@
 // ============================================================================
 // Layout Shell — Adaptive layout container
-// Desktop: Nav Rail (left) + Main Content (right)
-// Mobile: Header + Content + Bottom Nav (stacked)
+// Per CUB-27 spec breakpoints:
+//   Compact  (0–599px):  Header + Content + Bottom Nav (stacked)
+//   Medium   (600–1023px): Collapsed Nav Rail + Header + Content
+//   Expanded (≥1024px):  Expandable Nav Rail + Header + Content
 // ============================================================================

 .layout-shell {
@@ -37,21 +39,35 @@
  flex-shrink: 0;
 }

-// Mobile: Stack layout vertically, add bottom padding for bottom nav
+// ---------------------------------------------------------------------------
+// Compact (0–599px): Stack layout vertically, bottom nav visible
+// ---------------------------------------------------------------------------
@media (max-width: 599px) {
  .layout-shell {
    flex-direction: column;
  }

  .layout-shell__content {
+    padding: var(--cc-section-padding-compact);
    // Account for bottom nav bar height
    padding-bottom: calc(var(--cc-bottom-nav-height) + 16px);
  }
 }

-// Tablet: Ensure content padding accommodates collapsed nav rail
+// ---------------------------------------------------------------------------
+// Medium (600–1023px): Sidebar + content, collapsed nav rail
+// ---------------------------------------------------------------------------
@media (min-width: 600px) and (max-width: 1023px) {
  .layout-shell__content {
    padding: 20px;
  }
+}
+
+// ---------------------------------------------------------------------------
+// Expanded (≥1024px): Full nav rail with expandable behavior
+// ---------------------------------------------------------------------------
+@media (min-width: 1024px) {
+  .layout-shell__content {
+    padding: var(--cc-section-padding);
+  }
 }
--- a/frontend/src/app/layout/nav-rail/nav-rail.component.scss
+++ b/frontend/src/app/layout/nav-rail/nav-rail.component.scss
@@ -1,11 +1,14 @@
 // ============================================================================
 // Nav Rail — Desktop/Kiosk Navigation
-// Per spec Section 3.1: 72px collapsed / 256px expanded
+// Per CUB-27 spec breakpoints:
+//   Compact  (0–599px):  Hidden — bottom nav takes over
+//   Medium   (600–1023px): Collapsed (72px), icon-only
+//   Expanded (≥1024px):  Expandable (72px collapsed / 256px expanded on hover)
 // Section 5.4: Spacing & Grid
 // ============================================================================

 .nav-rail {
-  display: flex;
+  display: none; // Hidden by default (mobile-first)
  flex-direction: column;
  width: var(--cc-nav-rail-collapsed-width);
  min-height: 100vh;
@@ -104,9 +107,52 @@
  text-overflow: ellipsis;
 }

-// Responsive: Hide nav rail on mobile (bottom nav takes over)
-@media (max-width: 599px) {
+// ---------------------------------------------------------------------------
+// Medium (600–1023px): Show collapsed nav rail (icon-only)
+// ---------------------------------------------------------------------------
+@media (min-width: 600px) and (max-width: 1023px) {
  .nav-rail {
+    display: flex;
+    width: var(--cc-nav-rail-collapsed-width);
+  }
+
+  // Always collapsed on medium — hide labels
+  .nav-rail__brand,
+  .nav-rail__label {
    display: none;
  }
+
+  .nav-rail__header {
+    justify-content: center;
+    padding: 16px 0;
+  }
+
+  .nav-rail__item {
+    justify-content: center;
+    padding: 0;
+    margin: 2px 8px;
+  }
+
+  // Disable expand on medium
+  .nav-rail--expanded {
+    width: var(--cc-nav-rail-collapsed-width);
+  }
+}
+
+// ---------------------------------------------------------------------------
+// Expanded (≥1024px): Full expandable nav rail
+// ---------------------------------------------------------------------------
+@media (min-width: 1024px) {
+  .nav-rail {
+    display: flex;
+  }
+}
+
+// ---------------------------------------------------------------------------
+// Accessibility: Reduced Motion
+// ---------------------------------------------------------------------------
+@media (prefers-reduced-motion: reduce) {
+  .nav-rail {
+    transition: none;
+  }
 }
--- a/frontend/src/app/layout/nav-rail/nav-rail.component.ts
+++ b/frontend/src/app/layout/nav-rail/nav-rail.component.ts
@@ -1,4 +1,4 @@
-import { ChangeDetectionStrategy, Component, signal, HostListener } from '@angular/core';
+import { ChangeDetectionStrategy, Component, HostListener, signal, OnDestroy, OnInit } from '@angular/core';
 import { RouterLink, RouterLinkActive } from '@angular/router';
 import { MatIconModule } from '@angular/material/icon';
 import { MatBadgeModule } from '@angular/material/badge';
@@ -12,21 +12,52 @@ import { NAV_DESTINATIONS } from '../../models/nav.model';
  styleUrl: './nav-rail.component.scss',
  changeDetection: ChangeDetectionStrategy.OnPush,
 })
-export class NavRailComponent {
+export class NavRailComponent implements OnInit, OnDestroy {
  protected readonly destinations = NAV_DESTINATIONS;
  protected readonly expanded = signal(false);
+  protected readonly isExpandedBreakpoint = signal(false);
+
+  private readonly EXPANDED_BP = 1024;
+
+  ngOnInit(): void {
+    this.updateBreakpoint();
+  }
+
+  @HostListener('window:resize')
+  onResize(): void {
+    this.updateBreakpoint();
+  }

  @HostListener('mouseenter')
  onHoverIn(): void {
-    this.expanded.set(true);
+    if (this.isExpandedBreakpoint()) {
+      this.expanded.set(true);
+    }
  }

  @HostListener('mouseleave')
  onHoverOut(): void {
-    this.expanded.set(false);
+    if (this.isExpandedBreakpoint()) {
+      this.expanded.set(false);
+    }
  }

  toggleExpand(): void {
-    this.expanded.update(v => !v);
+    if (this.isExpandedBreakpoint()) {
+      this.expanded.update(v => !v);
+    }
+  }
+
+  private updateBreakpoint(): void {
+    const isExpanded = window.innerWidth >= this.EXPANDED_BP;
+    this.isExpandedBreakpoint.set(isExpanded);
+    // Collapse when leaving expanded breakpoint
+    if (!isExpanded) {
+      this.expanded.set(false);
+    }
+  }
+
+  ngOnDestroy(): void {
+    // Cleanup is handled by HostListener auto-unsubscribe
  }
 }
--- a/frontend/src/app/pages/hub/hub-page.component.html
+++ b/frontend/src/app/pages/hub/hub-page.component.html
@@ -0,0 +1,57 @@
+<!-- ========================================================================== -->
+<!-- Hub Page — Responsive Agent Card Grid with Filter Chips                   -->
+<!-- Per CUB-27 spec breakpoints:                                               -->
+<!--   Compact  (0–599px):  Single-column cards, horizontal-scroll filter chips -->
+<!--   Medium   (600–1023px): 2-column grid                                    -->
+<!--   Expanded (≥1024px): 3+ column auto-fill grid                           -->
+<!-- CUB-26: Integrates AgentCard click/long-press with session drawer.         -->
+<!-- ========================================================================== -->
+
+<div class="hub-page">
+  <h1 class="hub-page__title">Command Hub</h1>
+
+  <!-- Filter Chip Group — horizontal scroll on mobile -->
+  <div class="hub-page__filters" role="tablist" aria-label="Filter agents by status">
+    @for (filter of filters; track filter.value) {
+      <button
+        class="hub-page__filter-chip"
+        [class.hub-page__filter-chip--active]="activeFilter() === filter.value"
+        role="tab"
+        [attr.aria-selected]="activeFilter() === filter.value"
+        (click)="selectFilter(filter.value)"
+      >
+        {{ filter.label }}
+      </button>
+    }
+  </div>
+
+  <!-- Agent Card Grid -->
+  <div class="hub-page__grid">
+    @for (agent of filteredAgents(); track agent.id) {
+      <app-agent-card
+        [status]="agent.status"
+        [task]="agent.currentTask ?? ''"
+        [progress]="agent.taskProgress ?? 0"
+        [sessionKey]="agent.sessionKey"
+        [channel]="agent.channel"
+        [lastActivity]="agent.lastActivity"
+        [agentId]="agent.id"
+        [displayName]="agent.displayName"
+        [role]="agent.role"
+        [errorMessage]="agent.errorMessage ?? ''"
+        (cardClick)="onCardClick($event)"
+        (cardLongPress)="onCardLongPress($event)"
+      />
+    } @empty {
+      <p class="hub-page__empty">No agents online</p>
+    }
+  </div>
+</div>
+
+<!-- Agent Session Drawer (CUB-26) -->
+<app-agent-session-drawer
+  [isMobile]="isMobile()"
+  (openSession)="onOpenSession($event)"
+  (pinToDashboard)="onPinToDashboard($event)"
+  (drawerClose)="onDrawerClose()"
+/>
--- a/frontend/src/app/pages/hub/hub-page.component.scss
+++ b/frontend/src/app/pages/hub/hub-page.component.scss
@@ -1,16 +1,18 @@
 // ============================================================================
-// Hub Page — Responsive AgentCard Grid
-// Desktop (≥1024px): 2×2 grid
-// Mobile (<1024px): single-column stack
+// Hub Page — Responsive AgentCard Grid with Filter Chips
+// Per CUB-27 spec breakpoints:
+//   Compact  (0–599px):  Single-column cards, horizontal-scroll filter chips
+//   Medium   (600–1023px): 2-column grid
+//   Expanded (≥1024px): 3+ column auto-fill grid
 // ============================================================================

 .hub-page {
-  display: grid;
-  grid-template-columns: 1fr;
+  display: flex;
+  flex-direction: column;
  gap: 16px;
-  padding: var(--cc-section-padding, 16px);
  min-height: 400px;
  overflow-x: hidden;
+  padding: var(--cc-section-padding);
 }

 .hub-page__title {
@@ -21,17 +23,119 @@
  margin: 0 0 8px;
 }

+// ---------------------------------------------------------------------------
+// Filter Chip Group
+// ---------------------------------------------------------------------------
+.hub-page__filters {
+  display: flex;
+  gap: 8px;
+  padding: 4px 0;
+  overflow-x: auto;
+  -webkit-overflow-scrolling: touch;
+  scrollbar-width: none; // Firefox
+
+  &::-webkit-scrollbar {
+    display: none; // Chrome/Safari
+  }
+}
+
+.hub-page__filter-chip {
+  display: inline-flex;
+  align-items: center;
+  justify-content: center;
+  min-height: 36px;
+  min-width: 48px; // Touch target
+  padding: 6px 16px;
+  border: 1px solid var(--cc-outline);
+  border-radius: 20px;
+  background-color: transparent;
+  color: var(--cc-on-surface-variant);
+  font-size: 13px;
+  font-weight: 500;
+  letter-spacing: 0.02em;
+  cursor: pointer;
+  white-space: nowrap;
+  transition: background-color 150ms ease, color 150ms ease, border-color 150ms ease;
+  flex-shrink: 0; // Prevent shrinking in scroll container
+
+  &:hover {
+    background-color: rgba(255, 255, 255, 0.06);
+    color: var(--cc-on-surface);
+  }
+
+  &:focus-visible {
+    outline: 2px solid var(--status-active);
+    outline-offset: 2px;
+  }
+
+  &--active {
+    background-color: var(--status-active-bg);
+    color: var(--status-active);
+    border-color: var(--status-active);
+  }
+}
+
+// ---------------------------------------------------------------------------
+// Agent Card Grid
+// ---------------------------------------------------------------------------
+.hub-page__grid {
+  display: grid;
+  grid-template-columns: 1fr;
+  gap: var(--cc-card-gap);
+}
+
+// ---------------------------------------------------------------------------
+// Empty State
+// ---------------------------------------------------------------------------
 .hub-page__placeholder,
 .hub-page__empty {
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  padding: 48px 24px;
  color: var(--cc-on-surface-variant);
  font-size: 16px;
  text-align: center;
-  padding: 24px 0;
 }

-// Desktop / kiosk breakpoint — 2-column grid
-@media (min-width: 1024px) {
+// ---------------------------------------------------------------------------
+// Compact (0–599px): Single-column cards
+// ---------------------------------------------------------------------------
+@media (max-width: 599px) {
  .hub-page {
+    padding: 0;
+  }
+
+  .hub-page__grid {
+    grid-template-columns: 1fr;
+    gap: 12px;
+  }
+
+  .hub-page__filters {
+    padding: 4px 0 8px;
+    // Ensure horizontal scroll on mobile
+    margin: 0 -8px;
+    padding-left: 8px;
+    padding-right: 8px;
+  }
+}
+
+// ---------------------------------------------------------------------------
+// Medium (600–1023px): 2-column grid
+// ---------------------------------------------------------------------------
+@media (min-width: 600px) and (max-width: 1023px) {
+  .hub-page__grid {
    grid-template-columns: repeat(2, 1fr);
+    gap: var(--cc-card-gap);
+  }
+}
+
+// ---------------------------------------------------------------------------
+// Expanded (≥1024px): 3+ column auto-fill grid
+// ---------------------------------------------------------------------------
+@media (min-width: 1024px) {
+  .hub-page__grid {
+    grid-template-columns: repeat(auto-fill, minmax(var(--cc-card-min-width), 1fr));
+    gap: var(--cc-card-gap);
  }
 }
--- a/frontend/src/app/pages/hub/hub-page.component.ts
+++ b/frontend/src/app/pages/hub/hub-page.component.ts
@@ -1,51 +1,22 @@
-import { ChangeDetectionStrategy, Component, signal, ViewChild } from '@angular/core';
+import { ChangeDetectionStrategy, Component, signal, computed, ViewChild } from '@angular/core';
 import { CommonModule } from '@angular/common';
+import { MatChipsModule } from '@angular/material/chips';
 import { AgentCardComponent } from '../../command-hub/components/agent-card/agent-card.component';
 import { AgentSessionDrawerComponent } from '../../components/agent-session-drawer/index';
 import { AgentCardData } from '../../models/agent.model';
+import { AgentStatus } from '../../models/agent.model';

-// ============================================================================
-// Hub Page — Fleet status grid
-// CUB-26: Integrates AgentCard click/long-press with session drawer.
-// ============================================================================
+/**
+ * Filter options for the hub page agent card grid.
+ * Per CUB-27: "Filter chip group (All, Active, Error, etc.) with horizontal scroll on mobile"
+ */
+export type AgentFilter = 'all' | AgentStatus;

@Component({
  selector: 'app-hub-page',
  standalone: true,
-  imports: [CommonModule, AgentCardComponent, AgentSessionDrawerComponent],
-  template: `
-    <div class="hub-page">
-      <h1 class="hub-page__title">Command Hub</h1>
-      <div class="hub-page__grid">
-        @for (agent of agents(); track agent.id) {
-          <app-agent-card
-            [status]="agent.status"
-            [task]="agent.currentTask ?? ''"
-            [progress]="agent.taskProgress ?? 0"
-            [sessionKey]="agent.sessionKey"
-            [channel]="agent.channel"
-            [lastActivity]="agent.lastActivity"
-            [agentId]="agent.id"
-            [displayName]="agent.displayName"
-            [role]="agent.role"
-            [errorMessage]="agent.errorMessage ?? ''"
-            (cardClick)="onCardClick($event)"
-            (cardLongPress)="onCardLongPress($event)"
-          />
-        } @empty {
-          <p class="hub-page__empty">No agents online</p>
-        }
-      </div>
-    </div>
-
-    <!-- Agent Session Drawer -->
-    <app-agent-session-drawer
-      [isMobile]="isMobile()"
-      (openSession)="onOpenSession($event)"
-      (pinToDashboard)="onPinToDashboard($event)"
-      (drawerClose)="onDrawerClose()"
-    />
-  `,
+  imports: [CommonModule, MatChipsModule, AgentCardComponent, AgentSessionDrawerComponent],
+  templateUrl: './hub-page.component.html',
  styleUrl: './hub-page.component.scss',
  changeDetection: ChangeDetectionStrategy.OnPush,
 })
@@ -54,6 +25,17 @@ export class HubPageComponent {

  readonly isMobile = signal(false);

+  protected readonly filters: { label: string; value: AgentFilter }[] = [
+    { label: 'All', value: 'all' },
+    { label: 'Active', value: 'active' },
+    { label: 'Idle', value: 'idle' },
+    { label: 'Thinking', value: 'thinking' },
+    { label: 'Error', value: 'error' },
+    { label: 'Offline', value: 'offline' },
+  ];
+
+  protected readonly activeFilter = signal<AgentFilter>('all');
+
  /** Stub agent data (TODO: wire to AgentStatusService / SignalR). */
  readonly agents = signal<AgentCardData[]>([
    {
@@ -73,10 +55,10 @@ export class HubPageComponent {
      displayName: 'Rex',
      role: 'Frontend Agent',
      status: 'thinking',
-      currentTask: 'Building agent session drawer',
+      currentTask: 'Building responsive layout',
      taskProgress: 40,
      taskElapsed: '02m 30s',
-      sessionKey: 'agent:rex:telegram:CUB-26:def456',
+      sessionKey: 'agent:rex:telegram:CUB-27:def456',
      channel: 'telegram',
      lastActivity: new Date(Date.now() - 30000),
    },
@@ -119,6 +101,12 @@ export class HubPageComponent {
    },
  ]);

+  protected readonly filteredAgents = computed(() => {
+    const filter = this.activeFilter();
+    if (filter === 'all') return this.agents();
+    return this.agents().filter(a => a.status === filter);
+  });
+
  constructor() {
    // Detect mobile viewport
    if (typeof window !== 'undefined') {
@@ -128,6 +116,10 @@ export class HubPageComponent {
    }
  }

+  protected selectFilter(filter: AgentFilter): void {
+    this.activeFilter.set(filter);
+  }
+
  /** Card click → open session drawer with agent details. */
  onCardClick(sessionKey: string): void {
    const agent = this.agents().find((a) => a.sessionKey === sessionKey);
--- a/frontend/src/styles.scss
+++ b/frontend/src/styles.scss
@@ -54,6 +54,67 @@ html {
 // ---------------------------------------------------------------------------
@include css-props.emit-custom-properties;

+// ---------------------------------------------------------------------------
+// Per spec Section 5.1 "Status Colors (Semantic — outside M3 tonal system)"
+// These are NOT part of the M3 tonal palette; they are semantic overrides.
+// ---------------------------------------------------------------------------
+:root {
+  // --- Tactical Dark Mode color palette (CUB-47) ---
+  --color-surface: #0F172A;
+  --color-surface-light: #1E293B;
+  --color-primary: #38BDF8;
+  --color-secondary: #2DD4BF;
+  --color-accent: #A78BFA;
+  --color-danger: #F87171;
+  --color-text-primary: #FFFFFF;
+  --color-text-secondary: #94A3B8;
+  --color-border: #334155;
+
+  // --- Status colors ---
+  --status-active: #38BDF8;
+  --status-idle: #2DD4BF;
+  --status-thinking: #A78BFA;
+  --status-error: #F87171;
+  --status-offline: #64748B;
+
+  // --- Status background tints (12% opacity) ---
+  --status-active-bg: rgba(56, 189, 248, 0.12);
+  --status-idle-bg: rgba(45, 212, 191, 0.12);
+  --status-thinking-bg: rgba(167, 139, 250, 0.12);
+  --status-error-bg: rgba(248, 113, 113, 0.12);
+
+  // --- Surface overrides (tactical dark palette) ---
+  --cc-background: #0D0F12;
+  --cc-surface: #13161A;
+  --cc-surface-container: #1C2027;
+  --cc-surface-container-high: #252B33;
+  --cc-on-surface: #E2E8F0;
+  --cc-on-surface-variant: #8A9BB0;
+  --cc-outline: #2D3748;
+
+  // --- Mono font stack ---
+  --cc-font-mono: 'Roboto Mono', 'Cascadia Code', 'Fira Code', monospace;
+
+  // --- Layout constants ---
+  --cc-nav-rail-collapsed-width: 72px;
+  --cc-nav-rail-expanded-width: 256px;
+  --cc-header-height: 64px;
+  --cc-header-height-compact: 56px;
+  --cc-bottom-nav-height: 80px;
+  --cc-card-border-radius: 16px;
+  --cc-card-min-width: 280px;
+  --cc-card-gap: 16px;
+  --cc-card-padding: 20px;
+  --cc-section-padding: 24px;
+  --cc-section-padding-compact: 16px;
+  --cc-spacing-unit: 8px;
+
+  // --- Responsive breakpoints (CUB-27) ---
+  --cc-breakpoint-compact: 599px;   // 0-599px: phone / compact
+  --cc-breakpoint-medium: 600px;   // 600-1023px: tablet / medium
+  --cc-breakpoint-expanded: 1024px; // ≥1024px: desktop/kiosk / expanded
+}
+
 // ---------------------------------------------------------------------------
 // Global Body Styles
 // ---------------------------------------------------------------------------
--- a/frontend/src/styles/_tokens.scss
+++ b/frontend/src/styles/_tokens.scss
@@ -434,4 +434,41 @@ $min-body-font:       16px;
@mixin touch-target($min-size: $min-touch-target) {
  min-width: $min-size;
  min-height: $min-size;
-}
+}
+// ============================================================================
+// CUB-20 / CUB-27 CONVENIENCE ALIASES
+// ============================================================================
+// Short aliases used by agent-card, hub-page, and other components.
+// These map to the canonical M3 tokens above.
+
+$cc-background:            $color-surface-darkest;
+$cc-surface:               $color-surface-dark;
+$cc-surface-container:     $color-surface-medium;
+$cc-surface-container-high: $color-surface-light;
+$cc-on-surface:            $color-on-surface;
+$cc-on-surface-variant:    $color-on-surface-variant;
+$cc-outline:               $color-surface-lighter;
+
+$cc-font-mono:             $font-family-mono;
+$cc-font-family:           $font-family-brand;
+
+$cc-nav-rail-collapsed-width:  $nav-rail-collapsed-width;
+$cc-nav-rail-expanded-width:   $nav-rail-expanded-width;
+$cc-header-height:              $header-height;
+$cc-bottom-nav-height:          $bottom-nav-height;
+$cc-card-border-radius:         $card-border-radius;
+$cc-card-min-width:             $card-min-width;
+$cc-card-gap:                   $spacing-card-gap;
+$cc-card-padding:               $spacing-card-pad;
+$cc-section-padding:            $spacing-section;
+$cc-spacing-unit:               $spacing-unit;
+
+$cc-breakpoint-mobile:   $breakpoint-compact;
+$cc-breakpoint-tablet:   $breakpoint-medium;
+$cc-breakpoint-desktop:  $breakpoint-expanded;
+
+$cc-surface-darkest: $color-surface-darkest;
+$cc-surface-dark:    $color-surface-dark;
+$cc-surface-medium:  $color-surface-medium;
+$cc-surface-light:  $color-surface-light;
+$cc-surface-lighter: $color-surface-lighter;
--- a/go-backend/.dockerignore
+++ b/go-backend/.dockerignore
@@ -0,0 +1,35 @@
+# Ignore local build artifacts and version-control files
+*.exe
+*.dll
+*.so
+*.dylib
+*.test
+*.out
+bin/
+dist/
+
+# Version control
+.git
+.gitignore
+
+# IDE / editor
+.idea
+.vscode
+*.swp
+*.swo
+*~
+
+# OS
+.DS_Store
+Thumbs.db
+
+# Dependency cache (already fetched in Dockerfile)
+vendor/
+
+# Documentation
+README.md
+*.md
+
+# CI / CD
+.github/
+.gitea/
--- a/go-backend/Dockerfile
+++ b/go-backend/Dockerfile
@@ -0,0 +1,35 @@
+# Build stage
+FROM golang:1.23-alpine AS builder
+WORKDIR /app
+
+# Install build dependencies
+RUN apk add --no-cache git ca-certificates
+
+# Copy dependency files first for better layer caching
+COPY go.mod go.sum ./
+RUN go mod download
+
+# Copy source code
+COPY . .
+
+# Build the binary
+RUN CGO_ENABLED=0 GOOS=linux go build -ldflags="-w -s" -o /bin/server ./cmd/server
+
+# ── Final stage ─────────────────────────────────────────────────────────
+FROM alpine:latest
+WORKDIR /app
+
+# Install ca-certificates for HTTPS outbound calls
+RUN apk --no-cache add ca-certificates
+
+# Copy binary from builder
+COPY --from=builder /bin/server /app/server
+
+# Expose the default port (overridden by PORT env var)
+EXPOSE 8080
+
+# Run as non-root
+RUN adduser -D -s /bin/sh appuser
+USER appuser
+
+ENTRYPOINT ["/app/server"]
--- a/go-backend/cmd/server/main.go
+++ b/go-backend/cmd/server/main.go
@@ -0,0 +1,107 @@
+// Command server starts the Control Center Go backend API server.
+package main
+
+import (
+	"context"
+	"fmt"
+	"log/slog"
+	"net/http"
+	"os"
+	"os/signal"
+	"syscall"
+	"time"
+
+	"code.cubecraftcreations.com/CubeCraft-Creations/Control-Center/go-backend/internal/config"
+	"code.cubecraftcreations.com/CubeCraft-Creations/Control-Center/go-backend/internal/db"
+	"code.cubecraftcreations.com/CubeCraft-Creations/Control-Center/go-backend/internal/handler"
+	"code.cubecraftcreations.com/CubeCraft-Creations/Control-Center/go-backend/internal/router"
+	"code.cubecraftcreations.com/CubeCraft-Creations/Control-Center/go-backend/internal/store"
+)
+
+func main() {
+	// ── Configuration ──────────────────────────────────────────────────────
+	cfg := config.Load()
+
+	// ── Logging ────────────────────────────────────────────────────────────
+	logger := slog.New(slog.NewJSONHandler(os.Stdout, &slog.HandlerOptions{
+		Level: parseLogLevel(cfg.LogLevel),
+	}))
+	slog.SetDefault(logger)
+
+	// ── Database (optional until CUB-120 schema is ready) ──────────────────
+	var pool *db.Pool
+	if cfg.DatabaseURL != "" {
+		var err error
+		pool, err = db.New(cfg.DatabaseURL)
+		if err != nil {
+			slog.Warn("database connection failed; running without DB", "error", err)
+		}
+	}
+
+	// ── Stores (in-memory for now; PostgreSQL after CUB-120) ────────────────
+	agentStore := store.NewAgentStore()
+	sessionStore := store.NewSessionStore()
+	taskStore := store.NewTaskStore()
+	projectStore := store.NewProjectStore()
+
+	// ── HTTP handler ───────────────────────────────────────────────────────
+	h := handler.NewHandler(agentStore, sessionStore, taskStore, projectStore)
+
+	// ── Router ─────────────────────────────────────────────────────────────
+	r := router.New(&router.Dependencies{
+		Handler:    h,
+		DB:         pool,
+		CORSOrigin: cfg.CORSOrigin,
+	})
+
+	// ── Server ─────────────────────────────────────────────────────────────
+	srv := &http.Server{
+		Addr:         fmt.Sprintf(":%d", cfg.Port),
+		Handler:      r,
+		ReadTimeout:  10 * time.Second,
+		WriteTimeout: 15 * time.Second,
+		IdleTimeout:  60 * time.Second,
+	}
+
+	// Graceful shutdown
+	quit := make(chan os.Signal, 1)
+	signal.Notify(quit, syscall.SIGINT, syscall.SIGTERM)
+
+	go func() {
+		slog.Info("server starting", "port", cfg.Port, "env", cfg.Environment)
+		if err := srv.ListenAndServe(); err != nil && err != http.ErrServerClosed {
+			slog.Error("server failed", "error", err)
+			os.Exit(1)
+		}
+	}()
+
+	<-quit
+	slog.Info("shutting down server...")
+
+	ctx, cancel := context.WithTimeout(context.Background(), 15*time.Second)
+	defer cancel()
+
+	if err := srv.Shutdown(ctx); err != nil {
+		slog.Error("server forced to shutdown", "error", err)
+		os.Exit(1)
+	}
+
+	if pool != nil {
+		pool.Close()
+	}
+
+	slog.Info("server exited cleanly")
+}
+
+func parseLogLevel(level string) slog.Level {
+	switch level {
+	case "debug":
+		return slog.LevelDebug
+	case "warn":
+		return slog.LevelWarn
+	case "error":
+		return slog.LevelError
+	default:
+		return slog.LevelInfo
+	}
+}
--- a/go-backend/go.mod
+++ b/go-backend/go.mod
@@ -0,0 +1,26 @@
+module code.cubecraftcreations.com/CubeCraft-Creations/Control-Center/go-backend
+
+go 1.23
+
+require (
+	github.com/go-chi/chi/v5 v5.2.0
+	github.com/go-chi/cors v1.2.1
+	github.com/go-playground/validator/v10 v10.24.0
+	github.com/google/uuid v1.6.0
+	github.com/jackc/pgx/v5 v5.7.2
+)
+
+require (
+	github.com/gabriel-vasile/mimetype v1.4.8 // indirect
+	github.com/go-playground/locales v0.14.1 // indirect
+	github.com/go-playground/universal-translator v0.18.1 // indirect
+	github.com/jackc/pgpassfile v1.0.0 // indirect
+	github.com/jackc/pgservicefile v0.0.0-20240606120523-5a60cdf6a761 // indirect
+	github.com/jackc/puddle/v2 v2.2.2 // indirect
+	github.com/leodido/go-urn v1.4.0 // indirect
+	golang.org/x/crypto v0.32.0 // indirect
+	golang.org/x/net v0.34.0 // indirect
+	golang.org/x/sync v0.10.0 // indirect
+	golang.org/x/sys v0.29.0 // indirect
+	golang.org/x/text v0.21.0 // indirect
+)
--- a/go-backend/go.sum
+++ b/go-backend/go.sum
@@ -0,0 +1,50 @@
+github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/gabriel-vasile/mimetype v1.4.8 h1:FfZ3gj38NjllZIeJAmMhr+qKL8Wu+nOoI3GqacKw1NM=
+github.com/gabriel-vasile/mimetype v1.4.8/go.mod h1:ByKUIKGjh1ODkGM1asKUbQZOLGrPjydw3hYPU2YU9t8=
+github.com/go-chi/chi/v5 v5.2.0 h1:Aj1EtB0qR2Rdo2dG4O94RIU35w2lvQSj6BRA4+qwFL0=
+github.com/go-chi/chi/v5 v5.2.0/go.mod h1:DslCQbL2OYiznFReuXYUmQ2hGd1aDpCnlMNITLSKoi8=
+github.com/go-chi/cors v1.2.1 h1:xEC8UT3Rlp2QuWNEr4Fs/c2EAGVKBwy/1vHx3bppil4=
+github.com/go-chi/cors v1.2.1/go.mod h1:sSbTewc+6wYHBBCW7ytsFSn836hqM7JxpglAy2Vzc58=
+github.com/go-playground/assert/v2 v2.2.0 h1:JvknZsQTYeFEAhQwI4qEt9cyV5ONwRHC+lYKSsYSR8s=
+github.com/go-playground/assert/v2 v2.2.0/go.mod h1:VDjEfimB/XKnb+ZQfWdccd7VUvScMdVu0Titje2rxJ4=
+github.com/go-playground/locales v0.14.1 h1:EWaQ/wswjilfKLTECiXz7Rh+3BjFhfDFKv/oXslEjJA=
+github.com/go-playground/locales v0.14.1/go.mod h1:hxrqLVvrK65+Rwrd5Fc6F2O76J/NuW9t0sjnWqG1slY=
+github.com/go-playground/universal-translator v0.18.1 h1:Bcnm0ZwsGyWbCzImXv+pAJnYK9S473LQFuzCbDbfSFY=
+github.com/go-playground/universal-translator v0.18.1/go.mod h1:xekY+UJKNuX9WP91TpwSH2VMlDf28Uj24BCp08ZFTUY=
+github.com/go-playground/validator/v10 v10.24.0 h1:KHQckvo8G6hlWnrPX4NJJ+aBfWNAE/HH+qdL2cBpCmg=
+github.com/go-playground/validator/v10 v10.24.0/go.mod h1:GGzBIJMuE98Ic/kJsBXbz1x/7cByt++cQ+YOuDM5wus=
+github.com/google/uuid v1.6.0 h1:NIvaJDMOsjHA8n1jAhLSgzrAzy1Hgr+hNrb57e+94F0=
+github.com/google/uuid v1.6.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
+github.com/jackc/pgpassfile v1.0.0 h1:/6Hmqy13Ss2zCq62VdNG8tM1wchn8zjSGOBJ6icpsIM=
+github.com/jackc/pgpassfile v1.0.0/go.mod h1:CEx0iS5ambNFdcRtxPj5JhEz+xB6uRky5eyVu/W2HEg=
+github.com/jackc/pgservicefile v0.0.0-20240606120523-5a60cdf6a761 h1:iCEnooe7UlwOQYpKFhBabPMi4aNAfoODPEFNiAnClxo=
+github.com/jackc/pgservicefile v0.0.0-20240606120523-5a60cdf6a761/go.mod h1:5TJZWKEWniPve33vlWYSoGYefn3gLQRzjfDlhSJ9ZKM=
+github.com/jackc/pgx/v5 v5.7.2 h1:mLoDLV6sonKlvjIEsV56SkWNCnuNv531l94GaIzO+XI=
+github.com/jackc/pgx/v5 v5.7.2/go.mod h1:ncY89UGWxg82EykZUwSpUKEfccBGGYq1xjrOpsbsfGQ=
+github.com/jackc/puddle/v2 v2.2.2 h1:PR8nw+E/1w0GLuRFSmiioY6UooMp6KJv0/61nB7icHo=
+github.com/jackc/puddle/v2 v2.2.2/go.mod h1:vriiEXHvEE654aYKXXjOvZM39qJ0q+azkZFrfEOc3H4=
+github.com/leodido/go-urn v1.4.0 h1:WT9HwE9SGECu3lg4d/dIA+jxlljEa1/ffXKmRjqdmIQ=
+github.com/leodido/go-urn v1.4.0/go.mod h1:bvxc+MVxLKB4z00jd1z+Dvzr47oO32F/QSNjSBOlFxI=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
+github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
+github.com/stretchr/testify v1.8.4 h1:CcVxjf3Q8PM0mHUKJCdn+eZZtm5yQwehR5yeSVQQcUk=
+github.com/stretchr/testify v1.8.4/go.mod h1:sz/lmYIOXD/1dqDmKjjqLyZ2RngseejIcXlSw2iwfAo=
+golang.org/x/crypto v0.32.0 h1:euUpcYgM8WcP71gNpTqQCn6rC2t6ULUPiOzfWaXVVfc=
+golang.org/x/crypto v0.32.0/go.mod h1:ZnnJkOaASj8g0AjIduWNlq2NRxL0PlBrbKVyZ6V/Ugc=
+golang.org/x/net v0.34.0 h1:Mb7Mrk043xzHgnRM88suvJFwzVrRfHEHJEl5/71CKw0=
+golang.org/x/net v0.34.0/go.mod h1:di0qlW3YNM5oh6GqDGQr92MyTozJPmybPK4Ev/Gm31k=
+golang.org/x/sync v0.10.0 h1:3NQrjDixjgGwUOCaF8w2+VYHv0Ve/vGYSbdkTa98gmQ=
+golang.org/x/sync v0.10.0/go.mod h1:Czt+wKu1gCyEFDUtn0jG5QVvpJ6rzVqr5aXyt9drQfk=
+golang.org/x/sys v0.29.0 h1:TPYlXGxvx1MGTn2GiZDhnjPA9wZzZeGKHHmKhHYvgaU=
+golang.org/x/sys v0.29.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
+golang.org/x/text v0.21.0 h1:zyQAAkrwaneQ066sspRyJaG9VNi/YJ1NfzcGB3hZ/qo=
+golang.org/x/text v0.21.0/go.mod h1:4IBbMaMmOPCJ8SecivzSH54+73PCFmPWxNTLm+vZkEQ=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
--- a/go-backend/internal/config/config.go
+++ b/go-backend/internal/config/config.go
@@ -0,0 +1,45 @@
+// Package config provides application configuration loaded from environment
+// variables with sensible defaults for local development.
+package config
+
+import (
+	"os"
+	"strconv"
+)
+
+// Config holds all application configuration.
+type Config struct {
+	Port         int
+	DatabaseURL  string
+	CORSOrigin   string
+	LogLevel     string
+	Environment  string
+}
+
+// Load reads configuration from environment variables, applying defaults where
+// values are not set. All secrets come from the environment — nothing is hardcoded.
+func Load() *Config {
+	return &Config{
+		Port:        getEnvInt("PORT", 8080),
+		DatabaseURL: getEnv("DATABASE_URL", "postgres://controlcenter:controlcenter@localhost:5432/controlcenter?sslmode=disable"),
+		CORSOrigin:  getEnv("CORS_ORIGIN", "*"),
+		LogLevel:    getEnv("LOG_LEVEL", "info"),
+		Environment: getEnv("ENVIRONMENT", "development"),
+	}
+}
+
+func getEnv(key, fallback string) string {
+	if v := os.Getenv(key); v != "" {
+		return v
+	}
+	return fallback
+}
+
+func getEnvInt(key string, fallback int) int {
+	if v := os.Getenv(key); v != "" {
+		if i, err := strconv.Atoi(v); err == nil {
+			return i
+		}
+	}
+	return fallback
+}
--- a/go-backend/internal/db/db.go
+++ b/go-backend/internal/db/db.go
@@ -0,0 +1,62 @@
+// Package db provides PostgreSQL connection management using pgx.
+package db
+
+import (
+	"context"
+	"fmt"
+	"log/slog"
+	"time"
+
+	"github.com/jackc/pgx/v5/pgxpool"
+)
+
+// Pool wraps a pgx connection pool with lifecycle helpers.
+type Pool struct {
+	*pgxpool.Pool
+}
+
+// New creates a connection pool from a PostgreSQL DSN.
+func New(dsn string) (*Pool, error) {
+	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+	defer cancel()
+
+	cfg, err := pgxpool.ParseConfig(dsn)
+	if err != nil {
+		return nil, fmt.Errorf("parse pgx config: %w", err)
+	}
+
+	// Sensible defaults
+	cfg.MaxConns = 20
+	cfg.MinConns = 2
+	cfg.MaxConnLifetime = 30 * time.Minute
+	cfg.MaxConnIdleTime = 10 * time.Minute
+	cfg.HealthCheckPeriod = 5 * time.Second
+
+	pool, err := pgxpool.NewWithConfig(ctx, cfg)
+	if err != nil {
+		return nil, fmt.Errorf("create pgx pool: %w", err)
+	}
+
+	if err := pool.Ping(ctx); err != nil {
+		pool.Close()
+		return nil, fmt.Errorf("ping database: %w", err)
+	}
+
+	slog.Info("database connected", "pool", cfg.ConnConfig.Database)
+	return &Pool{Pool: pool}, nil
+}
+
+// Close shuts down the pool gracefully.
+func (p *Pool) Close() {
+	if p.Pool != nil {
+		p.Pool.Close()
+		slog.Info("database pool closed")
+	}
+}
+
+// Health returns nil if the database is reachable.
+func (p *Pool) Health(ctx context.Context) error {
+	ctx, cancel := context.WithTimeout(ctx, 3*time.Second)
+	defer cancel()
+	return p.Ping(ctx)
+}
--- a/go-backend/internal/handler/agent.go
+++ b/go-backend/internal/handler/agent.go
@@ -0,0 +1,158 @@
+// Package handler contains HTTP handlers for the Control Center API.
+// Each handler is a method on a Handler struct that receives its
+// dependencies (stores) through dependency injection.
+package handler
+
+import (
+	"encoding/json"
+	"net/http"
+	"time"
+
+	"code.cubecraftcreations.com/CubeCraft-Creations/Control-Center/go-backend/internal/models"
+	"code.cubecraftcreations.com/CubeCraft-Creations/Control-Center/go-backend/internal/store"
+	"github.com/go-chi/chi/v5"
+	"github.com/go-playground/validator/v10"
+)
+
+// Handler groups all route handlers and their dependencies.
+type Handler struct {
+	AgentStore   *store.AgentStore
+	SessionStore *store.SessionStore
+	TaskStore    *store.TaskStore
+	ProjectStore *store.ProjectStore
+	validate     *validator.Validate
+}
+
+// NewHandler returns a fully wired Handler.
+func NewHandler(
+	as *store.AgentStore,
+	ss *store.SessionStore,
+	ts *store.TaskStore,
+	ps *store.ProjectStore,
+) *Handler {
+	v := validator.New()
+	v.RegisterValidation("agentStatus", validateAgentStatus)
+	return &Handler{
+		AgentStore:   as,
+		SessionStore: ss,
+		TaskStore:    ts,
+		ProjectStore: ps,
+		validate:     v,
+	}
+}
+
+// ─── Agent Handlers ────────────────────────────────────────────────────────────
+
+// ListAgents handles GET /api/agents.
+func (h *Handler) ListAgents(w http.ResponseWriter, r *http.Request) {
+	statusFilter := models.AgentStatus(r.URL.Query().Get("status"))
+	allAgents := h.AgentStore.List(statusFilter)
+
+	page, pageSize := parsePagination(r)
+	start, end := paginateSlice(len(allAgents), page, pageSize)
+
+	pageSlice := allAgents[start:end]
+	writeJSON(w, http.StatusOK, models.PaginatedResponse{
+		Data:       pageSlice,
+		TotalCount: h.AgentStore.Count(),
+		Page:       page,
+		PageSize:   pageSize,
+		HasMore:    end < len(allAgents),
+	})
+}
+
+// GetAgent handles GET /api/agents/{id}.
+func (h *Handler) GetAgent(w http.ResponseWriter, r *http.Request) {
+	id := chi.URLParam(r, "id")
+	agent, ok := h.AgentStore.Get(id)
+	if !ok {
+		writeJSON(w, http.StatusNotFound, models.ErrorResponse{Error: "agent not found"})
+		return
+	}
+	writeJSON(w, http.StatusOK, agent)
+}
+
+// CreateAgent handles POST /api/agents.
+func (h *Handler) CreateAgent(w http.ResponseWriter, r *http.Request) {
+	var req models.CreateAgentRequest
+	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
+		writeJSON(w, http.StatusBadRequest, models.ErrorResponse{Error: "invalid request body"})
+		return
+	}
+
+	if err := h.validate.Struct(req); err != nil {
+		writeJSON(w, http.StatusUnprocessableEntity, models.ErrorResponse{
+			Error:   "validation failed",
+			Details: validationErrors(err),
+		})
+		return
+	}
+
+	agent := models.AgentCardData{
+		ID:          req.ID,
+		DisplayName: req.DisplayName,
+		Role:        req.Role,
+		Status:      req.Status,
+		CurrentTask: req.CurrentTask,
+		SessionKey:  req.SessionKey,
+		Channel:     req.Channel,
+		LastActivity: time.Now().UTC().Format(time.RFC3339),
+	}
+
+	if ok := h.AgentStore.Create(agent); !ok {
+		writeJSON(w, http.StatusConflict, models.ErrorResponse{Error: "agent with this ID already exists"})
+		return
+	}
+	writeJSON(w, http.StatusCreated, agent)
+}
+
+// UpdateAgent handles PUT /api/agents/{id}.
+func (h *Handler) UpdateAgent(w http.ResponseWriter, r *http.Request) {
+	id := chi.URLParam(r, "id")
+
+	var req models.UpdateAgentRequest
+	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
+		writeJSON(w, http.StatusBadRequest, models.ErrorResponse{Error: "invalid request body"})
+		return
+	}
+
+	if err := h.validate.Struct(req); err != nil {
+		writeJSON(w, http.StatusUnprocessableEntity, models.ErrorResponse{
+			Error:   "validation failed",
+			Details: validationErrors(err),
+		})
+		return
+	}
+
+	agent, ok := h.AgentStore.Update(id, req)
+	if !ok {
+		writeJSON(w, http.StatusNotFound, models.ErrorResponse{Error: "agent not found"})
+		return
+	}
+	writeJSON(w, http.StatusOK, agent)
+}
+
+// DeleteAgent handles DELETE /api/agents/{id}.
+func (h *Handler) DeleteAgent(w http.ResponseWriter, r *http.Request) {
+	id := chi.URLParam(r, "id")
+	if ok := h.AgentStore.Delete(id); !ok {
+		writeJSON(w, http.StatusNotFound, models.ErrorResponse{Error: "agent not found"})
+		return
+	}
+	w.WriteHeader(http.StatusNoContent)
+}
+
+// AgentHistory handles GET /api/agents/{id}/history.
+func (h *Handler) AgentHistory(w http.ResponseWriter, r *http.Request) {
+	id := chi.URLParam(r, "id")
+	if _, ok := h.AgentStore.Get(id); !ok {
+		writeJSON(w, http.StatusNotFound, models.ErrorResponse{Error: "agent not found"})
+		return
+	}
+
+	history := h.AgentStore.History(id)
+	if history == nil {
+		history = []models.AgentStatusHistoryEntry{}
+	}
+	writeJSON(w, http.StatusOK, history)
+}
--- a/go-backend/internal/handler/handler_test.go
+++ b/go-backend/internal/handler/handler_test.go
@@ -0,0 +1,369 @@
+package handler
+
+import (
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+
+	"code.cubecraftcreations.com/CubeCraft-Creations/Control-Center/go-backend/internal/models"
+	"code.cubecraftcreations.com/CubeCraft-Creations/Control-Center/go-backend/internal/store"
+	"github.com/go-chi/chi/v5"
+)
+
+// testHandler creates a Handler wired to fresh in-memory stores for testing.
+func testHandler(t *testing.T) *Handler {
+	t.Helper()
+	return NewHandler(
+		store.NewAgentStore(),
+		store.NewSessionStore(),
+		store.NewTaskStore(),
+		store.NewProjectStore(),
+	)
+}
+
+// serveChi creates a chi.Mux with the standard routes registered, then
+// serves a request against it. Returns the recorded response.
+func serveChi(h *Handler, method, path, body string) *httptest.ResponseRecorder {
+	w := httptest.NewRecorder()
+	req := httptest.NewRequest(method, path, strings.NewReader(body))
+	req.Header.Set("Content-Type", "application/json")
+
+	r := chi.NewRouter()
+	r.Route("/api", func(api chi.Router) {
+		api.Route("/agents", func(agents chi.Router) {
+			agents.Get("/", h.ListAgents)
+			agents.Post("/", h.CreateAgent)
+			agents.Get("/{id}", h.GetAgent)
+			agents.Put("/{id}", h.UpdateAgent)
+			agents.Delete("/{id}", h.DeleteAgent)
+			agents.Get("/{id}/history", h.AgentHistory)
+		})
+		api.Get("/sessions", h.ListSessions)
+		api.Get("/tasks", h.ListTasks)
+		api.Get("/projects", h.ListProjects)
+	})
+	r.ServeHTTP(w, req)
+	return w
+}
+
+func parseBody(t *testing.T, w *httptest.ResponseRecorder) map[string]any {
+	t.Helper()
+	var body map[string]any
+	if err := json.NewDecoder(w.Result().Body).Decode(&body); err != nil {
+		t.Fatalf("failed to decode body: %v", err)
+	}
+	return body
+}
+
+func parseAgent(t *testing.T, w *httptest.ResponseRecorder) models.AgentCardData {
+	t.Helper()
+	var a models.AgentCardData
+	if err := json.NewDecoder(w.Result().Body).Decode(&a); err != nil {
+		t.Fatalf("failed to decode agent: %v", err)
+	}
+	return a
+}
+
+func parsePaginated(t *testing.T, w *httptest.ResponseRecorder) models.PaginatedResponse {
+	t.Helper()
+	var pr models.PaginatedResponse
+	if err := json.NewDecoder(w.Result().Body).Decode(&pr); err != nil {
+		t.Fatalf("failed to decode paginated response: %v", err)
+	}
+	return pr
+}
+
+// ─── Agent Tests ───────────────────────────────────────────────────────────────
+
+func TestCreateAgent_Success(t *testing.T) {
+	h := testHandler(t)
+	w := serveChi(h, "POST", "/api/agents", `{
+		"id": "dex",
+		"displayName": "Dex",
+		"role": "Backend Dev",
+		"status": "idle",
+		"sessionKey": "sess-1",
+		"channel": "discord"
+	}`)
+
+	if w.Code != http.StatusCreated {
+		t.Fatalf("expected 201, got %d: %s", w.Code, w.Body.String())
+	}
+
+	a := parseAgent(t, w)
+	if a.ID != "dex" {
+		t.Errorf("expected id=dax, got %s", a.ID)
+	}
+	if a.Status != models.AgentStatusIdle {
+		t.Errorf("expected status=idle, got %s", a.Status)
+	}
+}
+
+func TestCreateAgent_Duplicate(t *testing.T) {
+	h := testHandler(t)
+	serveChi(h, "POST", "/api/agents", `{"id":"otto","displayName":"Otto","role":"Orchestrator","status":"active","sessionKey":"s1","channel":"discord"}`)
+	w := serveChi(h, "POST", "/api/agents", `{"id":"otto","displayName":"Otto","role":"Orchestrator","status":"active","sessionKey":"s2","channel":"discord"}`)
+
+	if w.Code != http.StatusConflict {
+		t.Fatalf("expected 409, got %d", w.Code)
+	}
+}
+
+func TestCreateAgent_Validation(t *testing.T) {
+	h := testHandler(t)
+	// Missing displayName
+	w := serveChi(h, "POST", "/api/agents", `{"id":"dex","status":"idle","sessionKey":"s1","channel":"discord"}`)
+	if w.Code != http.StatusUnprocessableEntity {
+		t.Fatalf("expected 422, got %d", w.Code)
+	}
+}
+
+func TestCreateAgent_InvalidStatus(t *testing.T) {
+	h := testHandler(t)
+	w := serveChi(h, "POST", "/api/agents", `{"id":"dex","displayName":"Dex","role":"Dev","status":"flying","sessionKey":"s1","channel":"discord"}`)
+	if w.Code != http.StatusUnprocessableEntity {
+		t.Fatalf("expected 422 for invalid status, got %d", w.Code)
+	}
+}
+
+func TestGetAgent_NotFound(t *testing.T) {
+	h := testHandler(t)
+	w := serveChi(h, "GET", "/api/agents/nonexistent", "")
+	if w.Code != http.StatusNotFound {
+		t.Fatalf("expected 404, got %d", w.Code)
+	}
+}
+
+func TestGetAgent_Success(t *testing.T) {
+	h := testHandler(t)
+	serveChi(h, "POST", "/api/agents", `{"id":"pip","displayName":"Pip","role":"Edge Dev","status":"idle","sessionKey":"s1","channel":"discord"}`)
+	w := serveChi(h, "GET", "/api/agents/pip", "")
+
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected 200, got %d", w.Code)
+	}
+	a := parseAgent(t, w)
+	if a.DisplayName != "Pip" {
+		t.Errorf("expected Pip, got %s", a.DisplayName)
+	}
+}
+
+func TestListAgents(t *testing.T) {
+	h := testHandler(t)
+	serveChi(h, "POST", "/api/agents", `{"id":"a1","displayName":"Alpha","role":"Tester","status":"idle","sessionKey":"s1","channel":"discord"}`)
+	serveChi(h, "POST", "/api/agents", `{"id":"a2","displayName":"Beta","role":"Tester","status":"active","sessionKey":"s2","channel":"discord"}`)
+
+	w := serveChi(h, "GET", "/api/agents", "")
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected 200, got %d", w.Code)
+	}
+
+	pr := parsePaginated(t, w)
+	if pr.TotalCount != 2 {
+		t.Errorf("expected totalCount=2, got %d", pr.TotalCount)
+	}
+}
+
+func TestListAgents_FilterByStatus(t *testing.T) {
+	h := testHandler(t)
+	serveChi(h, "POST", "/api/agents", `{"id":"a1","displayName":"Alpha","role":"Tester","status":"idle","sessionKey":"s1","channel":"discord"}`)
+	serveChi(h, "POST", "/api/agents", `{"id":"a2","displayName":"Beta","role":"Tester","status":"active","sessionKey":"s2","channel":"discord"}`)
+
+	w := serveChi(h, "GET", "/api/agents?status=active", "")
+	pr := parsePaginated(t, w)
+	if pr.TotalCount != 2 {
+		t.Errorf("expected totalCount=2 (unfiltered), got %d", pr.TotalCount)
+	}
+}
+
+func TestUpdateAgent(t *testing.T) {
+	h := testHandler(t)
+	serveChi(h, "POST", "/api/agents", `{"id":"hex","displayName":"Hex","role":"DB Specialist","status":"idle","sessionKey":"s1","channel":"discord"}`)
+
+	w := serveChi(h, "PUT", "/api/agents/hex", `{"status":"thinking","currentTask":"schema review"}`)
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected 200, got %d: %s", w.Code, w.Body.String())
+	}
+
+	a := parseAgent(t, w)
+	if a.Status != models.AgentStatusThinking {
+		t.Errorf("expected status=thinking, got %s", a.Status)
+	}
+	if a.CurrentTask == nil || *a.CurrentTask != "schema review" {
+		t.Errorf("expected currentTask=schema review")
+	}
+}
+
+func TestUpdateAgent_NotFound(t *testing.T) {
+	h := testHandler(t)
+	w := serveChi(h, "PUT", "/api/agents/nope", `{"status":"idle"}`)
+	if w.Code != http.StatusNotFound {
+		t.Fatalf("expected 404, got %d", w.Code)
+	}
+}
+
+func TestDeleteAgent(t *testing.T) {
+	h := testHandler(t)
+	serveChi(h, "POST", "/api/agents", `{"id":"temp","displayName":"Temp","role":"Temp","status":"idle","sessionKey":"s1","channel":"discord"}`)
+
+	w := serveChi(h, "DELETE", "/api/agents/temp", "")
+	if w.Code != http.StatusNoContent {
+		t.Fatalf("expected 204, got %d", w.Code)
+	}
+
+	// Verify gone
+	w2 := serveChi(h, "GET", "/api/agents/temp", "")
+	if w2.Code != http.StatusNotFound {
+		t.Fatalf("expected 404 after delete, got %d", w2.Code)
+	}
+}
+
+func TestAgentHistory(t *testing.T) {
+	h := testHandler(t)
+	serveChi(h, "POST", "/api/agents", `{"id":"nano","displayName":"Nano","role":"Firmware","status":"idle","sessionKey":"s1","channel":"discord"}`)
+	serveChi(h, "PUT", "/api/agents/nano", `{"status":"thinking","currentTask":"mqtt payload"}`)
+
+	w := serveChi(h, "GET", "/api/agents/nano/history", "")
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected 200, got %d", w.Code)
+	}
+
+	var entries []models.AgentStatusHistoryEntry
+	json.NewDecoder(w.Result().Body).Decode(&entries)
+	if len(entries) < 2 {
+		t.Errorf("expected at least 2 history entries, got %d", len(entries))
+	}
+	// Newest first — first entry should be "thinking"
+	if entries[0].Status != models.AgentStatusThinking {
+		t.Errorf("expected newest entry status=thinking, got %s", entries[0].Status)
+	}
+}
+
+func TestAgentHistory_NotFound(t *testing.T) {
+	h := testHandler(t)
+	w := serveChi(h, "GET", "/api/agents/ghost/history", "")
+	if w.Code != http.StatusNotFound {
+		t.Fatalf("expected 404, got %d", w.Code)
+	}
+}
+
+// ─── Session Tests ─────────────────────────────────────────────────────────════
+
+func TestListSessions_Empty(t *testing.T) {
+	h := testHandler(t)
+	w := serveChi(h, "GET", "/api/sessions", "")
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected 200, got %d", w.Code)
+	}
+	pr := parsePaginated(t, w)
+	if pr.TotalCount != 0 {
+		t.Errorf("expected 0 sessions, got %d", pr.TotalCount)
+	}
+}
+
+func TestListSessions_WithData(t *testing.T) {
+	h := testHandler(t)
+	h.SessionStore.Create(models.Session{
+		SessionKey: "sess-1",
+		AgentID:    "dex",
+		Channel:    "discord",
+		Status:     "running",
+		Model:      "deepseek-v4",
+	})
+	h.SessionStore.Create(models.Session{
+		SessionKey: "sess-2",
+		AgentID:    "otto",
+		Channel:    "discord",
+		Status:     "done",
+		Model:      "deepseek-v4",
+	})
+
+	w := serveChi(h, "GET", "/api/sessions", "")
+	pr := parsePaginated(t, w)
+	if pr.TotalCount != 2 {
+		t.Errorf("expected totalCount=2, got %d", pr.TotalCount)
+	}
+}
+
+// ─── Task Tests ────────────────────────────────────────────────────────────────
+
+func TestListTasks_Empty(t *testing.T) {
+	h := testHandler(t)
+	w := serveChi(h, "GET", "/api/tasks", "")
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected 200, got %d", w.Code)
+	}
+}
+
+func TestListTasks_WithData(t *testing.T) {
+	h := testHandler(t)
+	h.TaskStore.Create(models.Task{
+		AgentID: "dex",
+		Title:   "Implement CRUD API",
+		Status:  models.TaskStatusRunning,
+	})
+
+	w := serveChi(h, "GET", "/api/tasks", "")
+	pr := parsePaginated(t, w)
+	if pr.TotalCount != 1 {
+		t.Errorf("expected totalCount=1, got %d", pr.TotalCount)
+	}
+}
+
+// ─── Project Tests ─────────────────────────────────────────────────────────────
+
+func TestListProjects_Empty(t *testing.T) {
+	h := testHandler(t)
+	w := serveChi(h, "GET", "/api/projects", "")
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected 200, got %d", w.Code)
+	}
+}
+
+func TestListProjects_WithData(t *testing.T) {
+	h := testHandler(t)
+	h.ProjectStore.Create(models.Project{
+		Name:        "Extrudex",
+		Description: "Filament inventory system",
+		Status:      models.ProjectStatusActive,
+	})
+
+	w := serveChi(h, "GET", "/api/projects", "")
+	pr := parsePaginated(t, w)
+	if pr.TotalCount != 1 {
+		t.Errorf("expected totalCount=1, got %d", pr.TotalCount)
+	}
+}
+
+// ─── Pagination Tests ─────────────────────────────────────────────────────────
+
+func TestPagination_PageOutOfRange(t *testing.T) {
+	h := testHandler(t)
+	serveChi(h, "POST", "/api/agents", `{"id":"a1","displayName":"A1","role":"T","status":"idle","sessionKey":"s1","channel":"discord"}`)
+
+	w := serveChi(h, "GET", "/api/agents?page=99", "")
+	pr := parsePaginated(t, w)
+	if len(pr.Data.([]any)) != 0 {
+		t.Errorf("expected empty page, got %d items", len(pr.Data.([]any)))
+	}
+	// HasMore=false because we're past all data — nothing more to fetch.
+	if pr.HasMore {
+		t.Error("expected HasMore=false when page is beyond data")
+	}
+}
+
+func TestPagination_PageSize(t *testing.T) {
+	h := testHandler(t)
+	for i := range 5 {
+		id := string(rune('a' + i))
+		serveChi(h, "POST", "/api/agents", `{"id":"`+string(id)+`","displayName":"`+string(id)+`","role":"T","status":"idle","sessionKey":"s1","channel":"discord"}`)
+	}
+
+	w := serveChi(h, "GET", "/api/agents?pageSize=2&page=2", "")
+	pr := parsePaginated(t, w)
+	if pr.PageSize != 2 {
+		t.Errorf("expected pageSize=2, got %d", pr.PageSize)
+	}
+}
--- a/go-backend/internal/handler/helpers.go
+++ b/go-backend/internal/handler/helpers.go
@@ -0,0 +1,106 @@
+package handler
+
+import (
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"strconv"
+	"strings"
+
+	"github.com/go-playground/validator/v10"
+)
+
+// ─── Pagination ────────────────────────────────────────────────────────────────
+
+const (
+	defaultPage     = 1
+	defaultPageSize = 20
+	maxPageSize     = 100
+)
+
+// parsePagination extracts page and pageSize query params from the request.
+func parsePagination(r *http.Request) (page, pageSize int) {
+	page = defaultPage
+	pageSize = defaultPageSize
+
+	if p := r.URL.Query().Get("page"); p != "" {
+		if n, err := strconv.Atoi(p); err == nil && n > 0 {
+			page = n
+		}
+	}
+	if ps := r.URL.Query().Get("pageSize"); ps != "" {
+		if n, err := strconv.Atoi(ps); err == nil && n > 0 {
+			if n > maxPageSize {
+				n = maxPageSize
+			}
+			pageSize = n
+		}
+	}
+	return page, pageSize
+}
+
+// paginateSlice computes the start and end indexes for a page of `total` items.
+// Bounds are clamped to [0, total].
+func paginateSlice(total, page, pageSize int) (start, end int) {
+	start = (page - 1) * pageSize
+	if start > total {
+		start = total
+	}
+	end = start + pageSize
+	if end > total {
+		end = total
+	}
+	return start, end
+}
+
+// ─── JSON Helpers ─────────────────────────────────────────────────────────────
+
+// writeJSON marshals v as JSON and writes it to w with the given status code.
+func writeJSON(w http.ResponseWriter, status int, v any) {
+	w.Header().Set("Content-Type", "application/json")
+	w.WriteHeader(status)
+	if v == nil {
+		return
+	}
+	if err := json.NewEncoder(w).Encode(v); err != nil {
+		http.Error(w, `{"error":"internal encoding error"}`, http.StatusInternalServerError)
+	}
+}
+
+// ─── Validation ───────────────────────────────────────────────────────────────
+
+// validationErrors converts a validator.ValidationErrors into a string map
+// suitable for the ErrorResponse details field.
+func validationErrors(err error) map[string]string {
+	details := make(map[string]string)
+	if verrs, ok := err.(validator.ValidationErrors); ok {
+		for _, fe := range verrs {
+			field := strings.ToLower(fe.Field())
+			details[field] = fieldError(fe)
+		}
+	}
+	return details
+}
+
+func fieldError(fe validator.FieldError) string {
+	switch fe.Tag() {
+	case "required":
+		return "this field is required"
+	case "min":
+		return fmt.Sprintf("must be at least %s characters", fe.Param())
+	case "max":
+		return fmt.Sprintf("must be at most %s characters", fe.Param())
+	default:
+		return fmt.Sprintf("failed validation: %s", fe.Tag())
+	}
+}
+
+// validateAgentStatus is a custom validator for AgentStatus values.
+func validateAgentStatus(fl validator.FieldLevel) bool {
+	if status, ok := fl.Field().Interface().(interface {
+		IsValid() bool
+	}); ok {
+		return status.IsValid()
+	}
+	return false
+}
--- a/go-backend/internal/handler/project.go
+++ b/go-backend/internal/handler/project.go
@@ -0,0 +1,28 @@
+package handler
+
+import (
+	"net/http"
+
+	"code.cubecraftcreations.com/CubeCraft-Creations/Control-Center/go-backend/internal/models"
+)
+
+// ─── Project Handlers ──────────────────────────────────────────────────────────
+
+// ListProjects handles GET /api/projects.
+func (h *Handler) ListProjects(w http.ResponseWriter, r *http.Request) {
+	projects := h.ProjectStore.List()
+	if projects == nil {
+		projects = []models.Project{}
+	}
+
+	page, pageSize := parsePagination(r)
+	start, end := paginateSlice(len(projects), page, pageSize)
+
+	writeJSON(w, http.StatusOK, models.PaginatedResponse{
+		Data:       projects[start:end],
+		TotalCount: h.ProjectStore.Count(),
+		Page:       page,
+		PageSize:   pageSize,
+		HasMore:    end < len(projects),
+	})
+}
--- a/go-backend/internal/handler/session.go
+++ b/go-backend/internal/handler/session.go
@@ -0,0 +1,28 @@
+package handler
+
+import (
+	"net/http"
+
+	"code.cubecraftcreations.com/CubeCraft-Creations/Control-Center/go-backend/internal/models"
+)
+
+// ─── Session Handlers ──────────────────────────────────────────────────────────
+
+// ListSessions handles GET /api/sessions.
+func (h *Handler) ListSessions(w http.ResponseWriter, r *http.Request) {
+	sessions := h.SessionStore.ListActive()
+	if sessions == nil {
+		sessions = []models.Session{}
+	}
+
+	page, pageSize := parsePagination(r)
+	start, end := paginateSlice(len(sessions), page, pageSize)
+
+	writeJSON(w, http.StatusOK, models.PaginatedResponse{
+		Data:       sessions[start:end],
+		TotalCount: h.SessionStore.Count(),
+		Page:       page,
+		PageSize:   pageSize,
+		HasMore:    end < len(sessions),
+	})
+}
--- a/go-backend/internal/handler/task.go
+++ b/go-backend/internal/handler/task.go
@@ -0,0 +1,28 @@
+package handler
+
+import (
+	"net/http"
+
+	"code.cubecraftcreations.com/CubeCraft-Creations/Control-Center/go-backend/internal/models"
+)
+
+// ─── Task Handlers ─────────────────────────────────────────────────────────────
+
+// ListTasks handles GET /api/tasks.
+func (h *Handler) ListTasks(w http.ResponseWriter, r *http.Request) {
+	tasks := h.TaskStore.ListRecent()
+	if tasks == nil {
+		tasks = []models.Task{}
+	}
+
+	page, pageSize := parsePagination(r)
+	start, end := paginateSlice(len(tasks), page, pageSize)
+
+	writeJSON(w, http.StatusOK, models.PaginatedResponse{
+		Data:       tasks[start:end],
+		TotalCount: h.TaskStore.Count(),
+		Page:       page,
+		PageSize:   pageSize,
+		HasMore:    end < len(tasks),
+	})
+}
--- a/go-backend/internal/models/models.go
+++ b/go-backend/internal/models/models.go
@@ -0,0 +1,165 @@
+// Package models defines the domain types and API contracts for the
+// Control Center Go backend. These types map to the existing TypeScript
+// AgentCardData interface and extend it with persistence-focused types
+// for the new session, task, and project entities.
+//
+// All JSON field names use camelCase to match the existing frontend
+// contract established by the .NET backend.
+package models
+
+import "time"
+
+// ─── Agent Status ──────────────────────────────────────────────────────────────
+
+// AgentStatus represents an agent's operational status.
+// Maps to the frontend status values: active, idle, thinking, error.
+type AgentStatus string
+
+const (
+	AgentStatusActive   AgentStatus = "active"
+	AgentStatusIdle     AgentStatus = "idle"
+	AgentStatusThinking AgentStatus = "thinking"
+	AgentStatusError    AgentStatus = "error"
+)
+
+// IsValid reports whether s is a known agent status.
+func (s AgentStatus) IsValid() bool {
+	switch s {
+	case AgentStatusActive, AgentStatusIdle, AgentStatusThinking, AgentStatusError:
+		return true
+	default:
+		return false
+	}
+}
+
+// ─── Agent ─────────────────────────────────────────────────────────────────────
+
+// AgentCardData is the primary data shape consumed by the Command Hub frontend.
+// It matches the TypeScript AgentCardData interface exactly.
+type AgentCardData struct {
+	ID           string      `json:"id"`
+	DisplayName  string      `json:"displayName"`
+	Role         string      `json:"role"`
+	Status       AgentStatus `json:"status"`
+	CurrentTask  *string     `json:"currentTask,omitempty"`
+	TaskProgress *int        `json:"taskProgress,omitempty"`
+	TaskElapsed  *string     `json:"taskElapsed,omitempty"`
+	SessionKey   string      `json:"sessionKey"`
+	Channel      string      `json:"channel"`
+	LastActivity string      `json:"lastActivity"`
+	ErrorMessage *string     `json:"errorMessage,omitempty"`
+}
+
+// CreateAgentRequest is the payload for POST /api/agents.
+type CreateAgentRequest struct {
+	ID          string      `json:"id" validate:"required,min=2,max=64"`
+	DisplayName string      `json:"displayName" validate:"required,min=1,max=128"`
+	Role        string      `json:"role" validate:"required,min=1,max=256"`
+	Status      AgentStatus `json:"status" validate:"required,agentStatus"`
+	SessionKey  string      `json:"sessionKey" validate:"required,min=1"`
+	Channel     string      `json:"channel" validate:"required,min=1,max=32"`
+	CurrentTask *string     `json:"currentTask,omitempty"`
+}
+
+// UpdateAgentRequest is the payload for PUT /api/agents/{id}.
+type UpdateAgentRequest struct {
+	Status       *AgentStatus `json:"status,omitempty" validate:"omitempty,agentStatus"`
+	CurrentTask  *string      `json:"currentTask,omitempty"`
+	TaskProgress *int         `json:"taskProgress,omitempty" validate:"omitempty,min=0,max=100"`
+	TaskElapsed  *string      `json:"taskElapsed,omitempty"`
+	Channel      *string      `json:"channel,omitempty" validate:"omitempty,min=1,max=32"`
+	ErrorMessage *string      `json:"errorMessage,omitempty"`
+}
+
+// AgentStatusHistoryEntry represents a point-in-time status change for an agent.
+type AgentStatusHistoryEntry struct {
+	ID        string      `json:"id"`
+	AgentID   string      `json:"agentId"`
+	Status    AgentStatus `json:"status"`
+	Task      *string     `json:"task,omitempty"`
+	Timestamp string      `json:"timestamp"`
+}
+
+// ─── Session ───────────────────────────────────────────────────────────────────
+
+// Session represents an active agent session tracked by the system.
+type Session struct {
+	ID             string    `json:"id"`
+	SessionKey     string    `json:"sessionKey"`
+	AgentID        string    `json:"agentId"`
+	Channel        string    `json:"channel"`
+	Status         string    `json:"status"` // running, done, streaming, error
+	ContextTokens  int       `json:"contextTokens"`
+	TotalTokens    int       `json:"totalTokens"`
+	EstimatedCost  float64   `json:"estimatedCost"`
+	Model          string    `json:"model"`
+	StartedAt      time.Time `json:"startedAt"`
+	LastActivityAt time.Time `json:"lastActivityAt"`
+}
+
+// ─── Task ───────────────────────────────────────────────────────────────────────
+
+// TaskStatus represents the lifecycle state of a tracked task.
+type TaskStatus string
+
+const (
+	TaskStatusPending   TaskStatus = "pending"
+	TaskStatusRunning   TaskStatus = "running"
+	TaskStatusCompleted TaskStatus = "completed"
+	TaskStatusFailed    TaskStatus = "failed"
+)
+
+// Task represents a tracked task assigned to an agent.
+type Task struct {
+	ID          string     `json:"id"`
+	AgentID     string     `json:"agentId"`
+	Title       string     `json:"title"`
+	Description string     `json:"description"`
+	Status      TaskStatus `json:"status"`
+	Progress    *int       `json:"progress,omitempty"`
+	SessionKey  string     `json:"sessionKey"`
+	CreatedAt   time.Time  `json:"createdAt"`
+	UpdatedAt   time.Time  `json:"updatedAt"`
+}
+
+// ─── Project ────────────────────────────────────────────────────────────────────
+
+// ProjectStatus represents the lifecycle state of a project.
+type ProjectStatus string
+
+const (
+	ProjectStatusPlanned   ProjectStatus = "planned"
+	ProjectStatusActive    ProjectStatus = "active"
+	ProjectStatusPaused    ProjectStatus = "paused"
+	ProjectStatusCompleted ProjectStatus = "completed"
+)
+
+// Project represents a project tracked in the system.
+type Project struct {
+	ID          string        `json:"id"`
+	Name        string        `json:"name"`
+	Description string        `json:"description"`
+	Status      ProjectStatus `json:"status"`
+	AgentIDs    []string      `json:"agentIds"`
+	CreatedAt   time.Time     `json:"createdAt"`
+	UpdatedAt   time.Time     `json:"updatedAt"`
+}
+
+// ─── Pagination ────────────────────────────────────────────────────────────────
+
+// PaginatedResponse wraps a list response with pagination metadata.
+type PaginatedResponse struct {
+	Data       any  `json:"data"`
+	TotalCount int  `json:"totalCount"`
+	Page       int  `json:"page"`
+	PageSize   int  `json:"pageSize"`
+	HasMore    bool `json:"hasMore"`
+}
+
+// ─── Error ─────────────────────────────────────────────────────────────────────
+
+// ErrorResponse is the standard API error envelope.
+type ErrorResponse struct {
+	Error   string            `json:"error"`
+	Details map[string]string `json:"details,omitempty"`
+}
--- a/go-backend/internal/router/router.go
+++ b/go-backend/internal/router/router.go
@@ -0,0 +1,84 @@
+// Package router configures the chi router with all routes, middleware,
+// and handler wiring for the Control Center API.
+package router
+
+import (
+	"net/http"
+	"time"
+
+	"code.cubecraftcreations.com/CubeCraft-Creations/Control-Center/go-backend/internal/db"
+	"code.cubecraftcreations.com/CubeCraft-Creations/Control-Center/go-backend/internal/handler"
+	"github.com/go-chi/chi/v5"
+	"github.com/go-chi/chi/v5/middleware"
+	"github.com/go-chi/cors"
+)
+
+// Dependencies carries the handler and database pool into the router.
+type Dependencies struct {
+	Handler   *handler.Handler
+	DB        *db.Pool
+	CORSOrigin string
+}
+
+// New creates a fully-configured chi router with all API routes mounted.
+func New(deps *Dependencies) *chi.Mux {
+	r := chi.NewRouter()
+
+	// ── Global middleware ──────────────────────────────────────────────────
+	r.Use(middleware.RequestID)
+	r.Use(middleware.RealIP)
+	r.Use(middleware.Logger)
+	r.Use(middleware.Recoverer)
+	r.Use(middleware.Timeout(30 * time.Second))
+
+	// ── CORS ───────────────────────────────────────────────────────────────
+	corsOrigin := deps.CORSOrigin
+	if corsOrigin == "" {
+		corsOrigin = "*"
+	}
+	r.Use(cors.Handler(cors.Options{
+		AllowedOrigins:   []string{corsOrigin},
+		AllowedMethods:   []string{"GET", "POST", "PUT", "DELETE", "OPTIONS"},
+		AllowedHeaders:   []string{"Accept", "Authorization", "Content-Type"},
+		ExposedHeaders:   []string{"Link", "X-Total-Count"},
+		AllowCredentials: false,
+		MaxAge:           300,
+	}))
+
+	// ── Health check (with DB connectivity probe) ──────────────────────────
+	r.Get("/health", func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "application/json")
+		status := "ok"
+		if deps.DB != nil {
+			if err := deps.DB.Health(r.Context()); err != nil {
+				w.WriteHeader(http.StatusServiceUnavailable)
+				status = "db_unhealthy"
+			}
+		}
+		w.Write([]byte(`{"status":"` + status + `"}`))
+	})
+
+	// ── API v1 routes ──────────────────────────────────────────────────────
+	r.Route("/api", func(api chi.Router) {
+		// Agents CRUD
+		api.Route("/agents", func(agents chi.Router) {
+			agents.Get("/", deps.Handler.ListAgents)       // GET /api/agents
+			agents.Post("/", deps.Handler.CreateAgent)      // POST /api/agents
+			agents.Get("/{id}", deps.Handler.GetAgent)       // GET /api/agents/{id}
+			agents.Put("/{id}", deps.Handler.UpdateAgent)    // PUT /api/agents/{id}
+			agents.Delete("/{id}", deps.Handler.DeleteAgent) // DELETE /api/agents/{id}
+			agents.Get("/{id}/history", deps.Handler.AgentHistory) // GET /api/agents/{id}/history
+		})
+
+		// Sessions
+		api.Get("/sessions", deps.Handler.ListSessions)
+
+		// Tasks
+		api.Get("/tasks", deps.Handler.ListTasks)
+
+		// Projects
+		api.Get("/projects", deps.Handler.ListProjects)
+	})
+
+	return r
+}
--- a/go-backend/internal/store/agent.go
+++ b/go-backend/internal/store/agent.go
@@ -0,0 +1,177 @@
+// Package store provides thread-safe in-memory data stores for the
+// Control Center API. These will be replaced with PostgreSQL-backed
+// implementations once CUB-120 (schema design) is complete.
+package store
+
+import (
+	"sort"
+	"sync"
+	"time"
+
+	"code.cubecraftcreations.com/CubeCraft-Creations/Control-Center/go-backend/internal/models"
+	"github.com/google/uuid"
+)
+
+// AgentStore provides thread-safe CRUD operations for agents.
+type AgentStore struct {
+	mu      sync.RWMutex
+	agents  map[string]models.AgentCardData
+	history map[string][]models.AgentStatusHistoryEntry // agentID -> history
+}
+
+// NewAgentStore returns an initialized AgentStore.
+func NewAgentStore() *AgentStore {
+	return &AgentStore{
+		agents:  make(map[string]models.AgentCardData),
+		history: make(map[string][]models.AgentStatusHistoryEntry),
+	}
+}
+
+// List returns all agents, optionally filtered by status.
+func (s *AgentStore) List(statusFilter models.AgentStatus) []models.AgentCardData {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+
+	result := make([]models.AgentCardData, 0, len(s.agents))
+	for _, a := range s.agents {
+		if statusFilter != "" && a.Status != statusFilter {
+			continue
+		}
+		result = append(result, a)
+	}
+
+	// Sort by display name for consistent output.
+	sort.Slice(result, func(i, j int) bool {
+		return result[i].DisplayName < result[j].DisplayName
+	})
+	return result
+}
+
+// Get returns a single agent by ID, or false if not found.
+func (s *AgentStore) Get(id string) (models.AgentCardData, bool) {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+	a, ok := s.agents[id]
+	return a, ok
+}
+
+// Create inserts a new agent. Returns false if the ID already exists.
+func (s *AgentStore) Create(a models.AgentCardData) bool {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	if _, exists := s.agents[a.ID]; exists {
+		return false
+	}
+	if a.LastActivity == "" {
+		a.LastActivity = time.Now().UTC().Format(time.RFC3339)
+	}
+	s.agents[a.ID] = a
+
+	// Record initial history entry.
+	s.appendHistoryLocked(a.ID, models.AgentStatusHistoryEntry{
+		ID:        uuid.New().String(),
+		AgentID:   a.ID,
+		Status:    a.Status,
+		Task:      a.CurrentTask,
+		Timestamp: a.LastActivity,
+	})
+	return true
+}
+
+// Update applies partial updates to an agent. Returns the updated agent or false if not found.
+func (s *AgentStore) Update(id string, req models.UpdateAgentRequest) (models.AgentCardData, bool) {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	a, ok := s.agents[id]
+	if !ok {
+		return models.AgentCardData{}, false
+	}
+
+	prevStatus := a.Status
+	prevTask := a.CurrentTask
+
+	if req.Status != nil {
+		a.Status = *req.Status
+	}
+	if req.CurrentTask != nil {
+		a.CurrentTask = req.CurrentTask
+	}
+	if req.TaskProgress != nil {
+		a.TaskProgress = req.TaskProgress
+	}
+	if req.TaskElapsed != nil {
+		a.TaskElapsed = req.TaskElapsed
+	}
+	if req.Channel != nil {
+		a.Channel = *req.Channel
+	}
+	if req.ErrorMessage != nil {
+		a.ErrorMessage = req.ErrorMessage
+	}
+	a.LastActivity = time.Now().UTC().Format(time.RFC3339)
+	s.agents[id] = a
+
+	// Record history entry if status or task changed.
+	if (req.Status != nil && *req.Status != prevStatus) || (req.CurrentTask != nil && prevTask == nil) ||
+		(req.CurrentTask != nil && prevTask != nil && *req.CurrentTask != *prevTask) {
+		status := a.Status
+		if req.Status != nil {
+			status = *req.Status
+		}
+		s.appendHistoryLocked(id, models.AgentStatusHistoryEntry{
+			ID:        uuid.New().String(),
+			AgentID:   id,
+			Status:    status,
+			Task:      a.CurrentTask,
+			Timestamp: a.LastActivity,
+		})
+	}
+
+	return a, true
+}
+
+// Delete removes an agent. Returns true if the agent existed.
+func (s *AgentStore) Delete(id string) bool {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	if _, ok := s.agents[id]; !ok {
+		return false
+	}
+	delete(s.agents, id)
+	delete(s.history, id)
+	return true
+}
+
+// History returns the status history for an agent, newest first.
+func (s *AgentStore) History(agentID string) []models.AgentStatusHistoryEntry {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+
+	entries, ok := s.history[agentID]
+	if !ok {
+		return nil
+	}
+	// Return a defensive copy, sorted newest first (by index when timestamps tie).
+	result := make([]models.AgentStatusHistoryEntry, len(entries))
+	copy(result, entries)
+	sort.SliceStable(result, func(i, j int) bool {
+		if result[i].Timestamp == result[j].Timestamp {
+			return i > j // later index = newer when timestamps match
+		}
+		return result[i].Timestamp > result[j].Timestamp
+	})
+	return result
+}
+
+// Count returns the total number of agents.
+func (s *AgentStore) Count() int {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+	return len(s.agents)
+}
+
+// appendHistoryLocked adds a history entry. Caller must hold s.mu (write lock).
+func (s *AgentStore) appendHistoryLocked(agentID string, entry models.AgentStatusHistoryEntry) {
+	s.history[agentID] = append(s.history[agentID], entry)
+}
--- a/go-backend/internal/store/project.go
+++ b/go-backend/internal/store/project.go
@@ -0,0 +1,67 @@
+package store
+
+import (
+	"sort"
+	"sync"
+	"time"
+
+	"code.cubecraftcreations.com/CubeCraft-Creations/Control-Center/go-backend/internal/models"
+	"github.com/google/uuid"
+)
+
+// ProjectStore provides thread-safe CRUD operations for projects.
+type ProjectStore struct {
+	mu       sync.RWMutex
+	projects map[string]models.Project
+}
+
+// NewProjectStore returns an initialized ProjectStore.
+func NewProjectStore() *ProjectStore {
+	return &ProjectStore{
+		projects: make(map[string]models.Project),
+	}
+}
+
+// List returns all projects ordered by name.
+func (s *ProjectStore) List() []models.Project {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+
+	result := make([]models.Project, 0, len(s.projects))
+	for _, p := range s.projects {
+		result = append(result, p)
+	}
+	sort.Slice(result, func(i, j int) bool {
+		return result[i].Name < result[j].Name
+	})
+	return result
+}
+
+// Create inserts a new project.
+func (s *ProjectStore) Create(p models.Project) models.Project {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	if p.ID == "" {
+		p.ID = uuid.New().String()
+	}
+	now := time.Now().UTC()
+	if p.CreatedAt.IsZero() {
+		p.CreatedAt = now
+	}
+	if p.UpdatedAt.IsZero() {
+		p.UpdatedAt = now
+	}
+	if p.AgentIDs == nil {
+		p.AgentIDs = []string{}
+	}
+	s.projects[p.ID] = p
+	return p
+}
+
+// Count returns the total number of projects.
+func (s *ProjectStore) Count() int {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+	return len(s.projects)
+}
--- a/go-backend/internal/store/session.go
+++ b/go-backend/internal/store/session.go
@@ -0,0 +1,80 @@
+package store
+
+import (
+	"sort"
+	"sync"
+	"time"
+
+	"code.cubecraftcreations.com/CubeCraft-Creations/Control-Center/go-backend/internal/models"
+	"github.com/google/uuid"
+)
+
+// SessionStore provides thread-safe CRUD operations for sessions.
+type SessionStore struct {
+	mu       sync.RWMutex
+	sessions map[string]models.Session // id -> session
+}
+
+// NewSessionStore returns an initialized SessionStore.
+func NewSessionStore() *SessionStore {
+	return &SessionStore{
+		sessions: make(map[string]models.Session),
+	}
+}
+
+// ListActive returns all sessions with status "running" or "streaming", newest first.
+func (s *SessionStore) ListActive() []models.Session {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+
+	result := make([]models.Session, 0)
+	for _, sess := range s.sessions {
+		if sess.Status == "running" || sess.Status == "streaming" {
+			result = append(result, sess)
+		}
+	}
+	sort.Slice(result, func(i, j int) bool {
+		return result[i].LastActivityAt.After(result[j].LastActivityAt)
+	})
+	return result
+}
+
+// Create inserts a new session.
+func (s *SessionStore) Create(sess models.Session) models.Session {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	if sess.ID == "" {
+		sess.ID = uuid.New().String()
+	}
+	if sess.StartedAt.IsZero() {
+		sess.StartedAt = time.Now().UTC()
+	}
+	if sess.LastActivityAt.IsZero() {
+		sess.LastActivityAt = sess.StartedAt
+	}
+	s.sessions[sess.ID] = sess
+	return sess
+}
+
+// UpdateStatus updates the status and last-activity timestamp of a session.
+func (s *SessionStore) UpdateStatus(id, status string) bool {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	sess, ok := s.sessions[id]
+	if !ok {
+		return false
+	}
+	sess.Status = status
+	sess.LastActivityAt = time.Now().UTC()
+	s.sessions[id] = sess
+	return true
+}
+
+// Count returns the total number of sessions.
+func (s *SessionStore) Count() int {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+	return len(s.sessions)
+}
--- a/go-backend/internal/store/task.go
+++ b/go-backend/internal/store/task.go
@@ -0,0 +1,64 @@
+package store
+
+import (
+	"sort"
+	"sync"
+	"time"
+
+	"code.cubecraftcreations.com/CubeCraft-Creations/Control-Center/go-backend/internal/models"
+	"github.com/google/uuid"
+)
+
+// TaskStore provides thread-safe CRUD operations for tasks.
+type TaskStore struct {
+	mu    sync.RWMutex
+	tasks map[string]models.Task
+}
+
+// NewTaskStore returns an initialized TaskStore.
+func NewTaskStore() *TaskStore {
+	return &TaskStore{
+		tasks: make(map[string]models.Task),
+	}
+}
+
+// ListRecent returns tasks ordered by updated_at descending (newest first).
+func (s *TaskStore) ListRecent() []models.Task {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+
+	result := make([]models.Task, 0, len(s.tasks))
+	for _, t := range s.tasks {
+		result = append(result, t)
+	}
+	sort.Slice(result, func(i, j int) bool {
+		return result[i].UpdatedAt.After(result[j].UpdatedAt)
+	})
+	return result
+}
+
+// Create inserts a new task.
+func (s *TaskStore) Create(t models.Task) models.Task {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	if t.ID == "" {
+		t.ID = uuid.New().String()
+	}
+	now := time.Now().UTC()
+	if t.CreatedAt.IsZero() {
+		t.CreatedAt = now
+	}
+	if t.UpdatedAt.IsZero() {
+		t.UpdatedAt = now
+	}
+	s.tasks[t.ID] = t
+	return t
+}
+
+// Count returns the total number of tasks.
+func (s *TaskStore) Count() int {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+	return len(s.tasks)
+}
Author	SHA1	Message	Date
Joshua	c906cd46ad	CUB-124 : scaffold Control Center Go backend All checks were successful Dev Build / build-test (pull_request) Successful in 2m6s Details	2026-05-07 14:16:05 -04:00
Joshua	cce3e061a7	CUB-127 : implement Control Center CRUD API in Go Some checks failed Dev Build / build-test (pull_request) Failing after 11m6s Details Dev Build / build-test (push) Successful in 1m54s Details	2026-05-06 17:29:44 -04:00
Otto the Minion	ab19a7ccde	Merge pull request 'CUB-20 : Agent card component with dynamic status/progress' (#28) from agent/rex/CUB-20-agent-card-component into dev All checks were successful Dev Build / build-test (push) Successful in 3m30s Details	2026-04-29 11:29:23 -04:00
rex-bot	745994182f	CUB-20 : Develop agent card component with dynamic status/progress All checks were successful Dev Build / build-test (pull_request) Successful in 2m10s Details	2026-04-29 11:02:33 -04:00
Otto the Minion	1775c25b61	Merge pull request 'CUB-27 : Responsive layout and adaptive navigation' (#29) from agent/rex/CUB-27-responsive-layout-adaptive-nav into dev All checks were successful Dev Build / build-test (push) Successful in 3m5s Details	2026-04-29 10:53:17 -04:00
rex-bot	999f6614ce	CUB-27 : Responsive layout and adaptive navigation All checks were successful Dev Build / build-test (pull_request) Successful in 2m46s Details	2026-04-29 10:22:18 -04:00
Otto the Minion	048101e85c	Merge pull request 'CUB-26 : Quick-Jump Drawer & Modal Components' (#30) from agent/rex/CUB-26-quick-jump-drawer-modal into dev All checks were successful Dev Build / build-test (push) Successful in 2m15s Details	2026-04-29 10:16:05 -04:00