Add comprehensive tests for player API endpoints and player service functionality

- Implemented tests for player API endpoints including play, pause, stop, next, previous, seek, set volume, set mode, reload playlist, and get state.
- Added mock player service for testing API interactions.
- Created tests for player service methods including play, pause, stop playback, next, previous, seek, set volume, set mode, and reload playlist.
- Ensured proper handling of success, error, and edge cases in both API and service tests.
- Verified state management and serialization in player state tests.

app/main.py

@@ -6,10 +6,11 @@ from fastapi import FastAPI
 from fastapi.middleware.cors import CORSMiddleware
 
 from app.api import api_router
-from app.core.database import init_db
+from app.core.database import get_session_factory, init_db
 from app.core.logging import get_logger, setup_logging
 from app.middleware.logging import LoggingMiddleware
 from app.services.extraction_processor import extraction_processor
+from app.services.player import initialize_player_service, shutdown_player_service
 from app.services.socket import socket_manager
 
 
@@ -27,10 +28,18 @@ async def lifespan(_app: FastAPI) -> AsyncGenerator[None, None]:
     await extraction_processor.start()
     logger.info("Extraction processor started")
 
+    # Start the player service
+    await initialize_player_service(get_session_factory())
+    logger.info("Player service started")
+
     yield
 
     logger.info("Shutting down application")
 
+    # Stop the player service
+    await shutdown_player_service()
+    logger.info("Player service stopped")
+
     # Stop the extraction processor
     await extraction_processor.stop()
     logger.info("Extraction processor stopped")