fix(tests): Enhance event loop cleanup in app_instance fixture

tests/conftest.py

@@ -1,4 +1,5 @@
 import pytest
+import asyncio
 import subprocess
 import time
 import requests
@@ -49,9 +50,23 @@ def app_instance() -> Generator[App, None, None]:
  ):
   app = App()
   yield app
-  # Cleanup: Ensure asyncio loop is stopped
+  # Cleanup: Ensure asyncio loop is stopped and tasks are cancelled
-  if hasattr(app, '_loop') and app._loop.is_running():
+  if hasattr(app, '_loop'):
+   # 1. Identify all pending tasks in app._loop.
+   tasks = [t for t in asyncio.all_tasks(app._loop) if not t.done()]
+   # 2. Cancel them using task.cancel().
+   for task in tasks:
+    task.cancel()
+   # Stop background thread to take control of the loop thread-safely
+   if app._loop.is_running():
     app._loop.call_soon_threadsafe(app._loop.stop)
+    if hasattr(app, '_loop_thread') and app._loop_thread.is_alive():
+     app._loop_thread.join(timeout=2.0)
+   # 3. Wait for them to complete using loop.run_until_complete(asyncio.gather(*tasks, return_exceptions=True)).
+   if tasks:
+    app._loop.run_until_complete(asyncio.gather(*tasks, return_exceptions=True))
+   # 4. Then stop the loop.
+   app._loop.stop()
 
 @pytest.fixture
 def mock_app(app_instance: App) -> App: