feat(actor): Storage.deleteAll for match-end room cleanup

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

Author: ImriKochWix

src/actor.ts

@@ -31,6 +31,9 @@ export interface Storage {
   get<T>(key: string): Promise<T | undefined>;
   put(key: string, value: unknown): Promise<void>;
   delete(key: string): Promise<boolean>;
+  /** Wipe the room's entire persisted storage (match-end cleanup). Safe: a
+   *  later rejoin re-bootstraps exactly like a brand-new room. */
+  deleteAll(): Promise<void>;
 }