refactor: Update exception handling parameters in context managers for consistency

src/error_handler.py

@@ -245,7 +245,7 @@ class OperationTimer:
         self.start_time = time.time()
         return self
 
-    def __exit__(self, exc_type, exc_val, exc_tb):
+    def __exit__(self, _exc_type, _exc_val, _exc_tb):
         """End timing and check for performance issues."""
         import time