CUB-45: AgentCard final integration with sub-components

- Assemble AgentCard from AgentStatusBadge, TaskProgressBar, QuickJumpButton
- All 6 inputs functional: status, task, progress, sessionKey, channel, lastActivity
- Left-border accent matches status color (Active: #38BDF8, Idle: #2DD4BF, Thinking: #A78BFA, Error: #F87171)
- Accessibility: role="article" on card, aria-labels on all sections
- Uses tactical dark mode CSS variables from CUB-47
- Added @Input() to QuickJumpButton sessionKey for parent binding
- JumpClick output forwarded from AgentCard
- Build passes, type checking passes

frontend/src/app/components/agent-card/agent-card.component.html

@@ -0,0 +1,99 @@
+<!-- ============================================================================
+  Agent Card — Final Integration (CUB-45)
+  Assembles: AgentStatusBadge, TaskProgressBar, QuickJumpButton
+  Layout: left-border accent, aria-labels, role="article"
+  ========================================================================== -->
+
+<article
+  class="agent-card"
+  [class]="'agent-card--' + status()"
+  [attr.aria-label]="'Agent card: ' + status() + ' status, task: ' + (task() || 'none')"
+  [attr.role]="'article'"
+  [style.--agent-status-color]="statusColorVar()"
+  [style.--agent-status-bg]="statusBgVar()"
+>
+  <!-- Left border accent (4px, matching status color) -->
+  <div
+    class="agent-card__accent"
+    [attr.aria-hidden]="'true'"
+  ></div>
+
+  <!-- Card body -->
+  <div class="agent-card__body">
+
+    <!-- Header row: Status Badge + channel + last activity -->
+    <div class="agent-card__header">
+      <div class="agent-card__status-row">
+        <!-- Sub-component: Agent Status Badge -->
+        <app-agent-status-badge
+          [status]="status()"
+          [attr.aria-label]="status() + ' status'"
+        />
+      </div>
+      <div class="agent-card__meta">
+        @if (channel()) {
+          <span
+            class="agent-card__channel text-mono"
+            [attr.aria-label]="'Channel: ' + channel()"
+          >
+            <mat-icon
+              class="agent-card__channel-icon"
+              fontIcon="forum"
+              [inline]="true"
+              [attr.aria-hidden]="'true'"
+            ></mat-icon>
+            {{ channel() }}
+          </span>
+        }
+        <span
+          class="agent-card__last-activity text-mono"
+          [attr.aria-label]="'Last activity: ' + lastActivityText()"
+        >
+          {{ lastActivityText() }}
+        </span>
+      </div>
+    </div>
+
+    <!-- Task description -->
+    @if (task()) {
+      <p
+        class="agent-card__task"
+        [attr.aria-label]="'Current task: ' + task()"
+      >
+        {{ task() }}
+      </p>
+    }
+
+    <!-- Sub-component: Task Progress Bar -->
+    @if (showProgress()) {
+      <div
+        class="agent-card__progress"
+        [attr.aria-label]="'Task progress: ' + progress() + '%'"
+      >
+        <app-task-progress-bar
+          [progress]="progress()"
+          [showElapsed]="showElapsed()"
+        />
+      </div>
+    }
+
+    <!-- Footer: session key (truncated) + Quick-Jump button -->
+    <div class="agent-card__footer">
+      <span
+        class="agent-card__session text-mono"
+        [matTooltip]="sessionKey()"
+        [attr.aria-label]="'Session key: ' + sessionKey()"
+      >
+        {{ truncatedSessionKey() }}
+      </span>
+
+      <!-- Sub-component: Quick-Jump Button -->
+      <app-quick-jump-button
+        [sessionKey]="sessionKey()"
+        (jumpClick)="onJumpClick($event)"
+        [attr.aria-label]="'Jump to agent session'"
+      />
+    </div>
+
+  </div>
+</article>