Remove unused Subscription type

Author: wixysam

src/modules/entities.types.ts

@@ -22,11 +22,6 @@ export interface RealtimeEvent {
  */
 export type RealtimeCallback = (event: RealtimeEvent) => void;
 
-/**
- * Function returned from subscribe, call it to unsubscribe.
- */
-export type Subscription = () => void;
-
 /**
  * Entity handler providing CRUD operations for a specific entity type.
  *