feat: improve SSE broadcasting for weather sessions with enhanced error handling and connection management

src/app/api/weather/[id]/subscribe/route.ts

@@ -98,25 +98,38 @@ export async function GET(request: Request, { params }: { params: Promise<{ id:
 
 // Helper to broadcast to all connections (called from actions)
 export function broadcastToWeatherSession(sessionId: string, event: object) {
+  try {
     const sessionConnections = connections.get(sessionId);
     if (!sessionConnections || sessionConnections.size === 0) {
+      // No active connections, event will be picked up by polling
+      console.log(`[SSE Broadcast] No connections for session ${sessionId}, will be picked up by polling`);
       return;
     }
 
+    console.log(`[SSE Broadcast] Broadcasting to ${sessionConnections.size} connections for session ${sessionId}`);
+
     const encoder = new TextEncoder();
     const message = encoder.encode(`data: ${JSON.stringify(event)}\n\n`);
 
+    let sentCount = 0;
     for (const controller of sessionConnections) {
       try {
         controller.enqueue(message);
-    } catch {
+        sentCount++;
+      } catch (error) {
         // Connection might be closed, remove it
+        console.log(`[SSE Broadcast] Failed to send, removing connection:`, error);
         sessionConnections.delete(controller);
       }
     }
 
+    console.log(`[SSE Broadcast] Sent to ${sentCount} connections`);
+
     // Clean up empty sets
     if (sessionConnections.size === 0) {
       connections.delete(sessionId);
     }
+  } catch (error) {
+    console.error('[SSE Broadcast] Error broadcasting:', error);
+  }
 }