release: bump version to 0.52.0

backend/app/services/collectors/aisstream.py

@@ -138,7 +138,7 @@ class AISStreamCollector(BaseCollector):
 
         try:
             import websockets
-        except ImportError as exc:
+        except ImportError:
             return {"status": "failed", "error": "Python package 'websockets' is required for AISStream"}
 
         start_time = datetime.now(UTC)