add export for Invalidator type

src/runtime/store/index.ts

@@ -10,7 +10,7 @@ export type Unsubscriber = () => void;
 export type Updater<T> = (value: T) => T;
 
 /** Cleanup logic callback. */
-type Invalidator<T> = (value?: T) => void;
+export type Invalidator<T> = (value?: T) => void;
 
 /** Start and stop notification callbacks. */
 export type StartStopNotifier<T> = (set: Subscriber<T>) => Unsubscriber | void;