refactor: remove unnecessary get_session_factory usage

- Updated rooms_list endpoint to use injected session dependency
- Removed get_session_factory import from views/rooms.py
- Updated test_pipeline_main_file.py to use mock session instead of get_session_factory
- Pipeline files keep their get_session_factory usage as they manage long-running operations

server/tests/test_pipeline_main_file.py

@@ -624,10 +624,11 @@ async def test_pipeline_file_process_no_transcript():
 
         # Should raise an exception for missing transcript when get_transcript is called
         with pytest.raises(Exception, match="Transcript not found"):
-            from reflector.db import get_session_factory
+            # Use a mock session - the controller is mocked to return None anyway
+            from unittest.mock import MagicMock
 
-            async with get_session_factory()() as session:
-                await pipeline.get_transcript(session)
+            mock_session = MagicMock()
+            await pipeline.get_transcript(mock_session)
 
 
 @pytest.mark.asyncio