fix(controller): Add stop_services() and dialog imports for GUI decoupling

- Add AppController.stop_services() to clean up AI client and event loop
- Add ConfirmDialog, MMAApprovalDialog, MMASpawnApprovalDialog imports to gui_2.py
- Fix test mocks for MMA dashboard and approval indicators
- Add retry logic to conftest.py for Windows file lock cleanup

src/app_controller.py

@@ -418,6 +418,15 @@ class AppController:
   self._loop_thread = threading.Thread(target=self._run_event_loop, daemon=True)
   self._loop_thread.start()
 
+ def stop_services(self) -> None:
+  """Stops background threads and cleans up resources."""
+  import ai_client
+  ai_client.cleanup()
+  if self._loop and self._loop.is_running():
+   self._loop.call_soon_threadsafe(self._loop.stop)
+  if self._loop_thread and self._loop_thread.is_alive():
+   self._loop_thread.join(timeout=2.0)
+
  def _init_ai_and_hooks(self, app: Any = None) -> None:
   import api_hooks
   ai_client.set_provider(self._current_provider, self._current_model)