chore(backend): standardize multiline formatting across modules

Reformatted multiline function calls, object definitions, and queries for improved code readability and consistency. Adjusted imports and constraints where necessary.

backend/app/services/event_bus.py

@@ -54,22 +54,18 @@ class EventBusError(Exception):
     """Base exception for EventBus errors."""
 
 
-
 class EventBusConnectionError(EventBusError):
     """Raised when connection to Redis fails."""
 
 
-
 class EventBusPublishError(EventBusError):
     """Raised when publishing an event fails."""
 
 
-
 class EventBusSubscriptionError(EventBusError):
     """Raised when subscribing to channels fails."""
 
 
-
 class EventBus:
     """
     EventBus for Redis Pub/Sub communication.