chore: merge blocksuite source code (#9213)

blocksuite/playground/apps/starter/data/utils.ts

@@ -0,0 +1,8 @@
+import type { DocCollection } from '@blocksuite/store';
+
+export interface InitFn {
+  (collection: DocCollection, docId: string): Promise<void> | void;
+  id: string;
+  displayName: string;
+  description: string;
+}