fix(test): make queue completion test more robust with polling loop

apps/coordinator/tests/test_coordinator.py

@@ -601,9 +601,21 @@ class TestCoordinatorIntegration:
         coordinator = Coordinator(queue_manager=queue_manager, poll_interval=0.02)
 
         task = asyncio.create_task(coordinator.start())
-        await asyncio.sleep(0.5)  # Allow time for processing
-        await coordinator.stop()
 
+        # Poll for completion with timeout instead of fixed sleep
+        deadline = asyncio.get_event_loop().time() + 5.0  # 5 second timeout
+        while asyncio.get_event_loop().time() < deadline:
+            all_completed = True
+            for i in range(157, 162):
+                item = queue_manager.get_item(i)
+                if item is None or item.status != QueueItemStatus.COMPLETED:
+                    all_completed = False
+                    break
+            if all_completed:
+                break
+            await asyncio.sleep(0.05)
+
+        await coordinator.stop()
         task.cancel()
         try:
             await task