fix: improve maintenance and synchronize live conversations

backend/app/repositories/customer.py

@@ -56,7 +56,7 @@ class CustomerRepository:
             ).first()
             return customer
         except Exception as e:
-            logger.error(f"Error getting customer by email: {str(e)}")
+            logger.error(f"Error getting customer by email: {type(e).__name__}")
             return None
 
     def get_customer_by_phone(