feat(CUB-55): add SendStatusUpdate method to AgentStatusHub

backend/ControlCenter/Hubs/AgentStatusHub.cs

@@ -37,6 +37,33 @@ public class AgentStatusHub : Hub<IAgentStatusClient>
         _logger = logger;
     }
 
+    /// <summary>
+    /// Broadcasts an agent status update to all connected clients.
+    ///
+    /// <para>
+    /// Any connected client (or server-side caller) can invoke this method
+    /// to push a status update to every subscriber. The DTO is converted to
+    /// an <see cref="AgentStatusUpdate"/> record and relayed through the
+    /// <see cref="IAgentStatusClient.AgentStatusChanged"/> callback.
+    /// </para>
+    /// </summary>
+    /// <param name="update">The agent status update DTO to broadcast.</param>
+    public async Task SendStatusUpdate(AgentStatusUpdateDto update)
+    {
+        _logger.LogInformation(
+            "Broadcasting status update for agent {AgentId}: {Status}",
+            update.AgentId, update.Status);
+
+        var agentUpdate = update.ToUpdate();
+
+        // Broadcast to all connected clients
+        await Clients.All.AgentStatusChanged(agentUpdate);
+
+        // Also push to the specific agent's group
+        var agentGroup = AgentGroupName(update.AgentId);
+        await Clients.Group(agentGroup).AgentStatusChanged(agentUpdate);
+    }
+
     /// <summary>
     /// Adds the calling connection to the fleet group.
     /// Once joined, the client will receive all agent status changes