Add comprehensive tests for playlist service and refactor socket service tests

- Introduced a new test suite for the PlaylistService covering various functionalities including creation, retrieval, updating, and deletion of playlists.
- Added tests for handling sounds within playlists, ensuring correct behavior when adding/removing sounds and managing current playlists.
- Refactored socket service tests for improved readability by adjusting function signatures.
- Cleaned up unnecessary whitespace in sound normalizer and sound scanner tests for consistency.
- Enhanced audio utility tests to ensure accurate hash and size calculations, including edge cases for nonexistent files.
- Removed redundant blank lines in cookie utility tests for cleaner code.

app/api/v1/auth.py

@@ -28,7 +28,7 @@ from app.services.auth import AuthService
 from app.services.oauth import OAuthService
 from app.utils.auth import JWTUtils, TokenUtils
 
-router = APIRouter()
+router = APIRouter(prefix="/auth", tags=["authentication"])
 logger = get_logger(__name__)
 
 # Global temporary storage for OAuth codes (in production, use Redis with TTL)
@@ -459,7 +459,8 @@ async def generate_api_token(
         )
     except Exception as e:
         logger.exception(
-            "Failed to generate API token for user: %s", current_user.email,
+            "Failed to generate API token for user: %s",
+            current_user.email,
         )
         raise HTTPException(
             status_code=status.HTTP_500_INTERNAL_SERVER_ERROR,
@@ -495,7 +496,8 @@ async def revoke_api_token(
         await auth_service.revoke_api_token(current_user)
     except Exception as e:
         logger.exception(
-            "Failed to revoke API token for user: %s", current_user.email,
+            "Failed to revoke API token for user: %s",
+            current_user.email,
         )
         raise HTTPException(
             status_code=status.HTTP_500_INTERNAL_SERVER_ERROR,