fix(editor): cleanup transformer middleware slot subscriptions (#12630)

<!-- This is an auto-generated comment: release notes by coderabbit.ai -->

## Summary by CodeRabbit

- **New Features**
  - Improved resource management by introducing explicit cleanup for various middleware components, ensuring that resources are properly released when no longer needed.

- **Refactor**
  - Updated middleware logic to support cleanup functions, enhancing the stability and performance of the application by preventing potential memory leaks.

- **Chores**
  - Enhanced lifecycle management in core systems to automatically dispose of resources when appropriate.

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

blocksuite/framework/store/src/transformer/middleware.ts

@@ -113,6 +113,8 @@ type TransformerMiddlewareOptions = {
   transformerConfigs: Map<string, unknown>;
 };
 
+type TransformerMiddlewareCleanup = () => void;
+
 export type TransformerMiddleware = (
   options: TransformerMiddlewareOptions
-) => void;
+) => void | TransformerMiddlewareCleanup;

blocksuite/framework/store/src/transformer/transformer.ts

@@ -1,3 +1,4 @@
+import { DisposableGroup } from '@blocksuite/global/disposable';
 import { BlockSuiteError, ErrorCode } from '@blocksuite/global/exceptions';
 import { nextTick } from '@blocksuite/global/utils';
 import { Subject } from 'rxjs';
@@ -67,6 +68,8 @@ export class Transformer {
 
   private readonly _docCRUD: DocCRUD;
 
+  private readonly _disposables: DisposableGroup = new DisposableGroup();
+
   private readonly _slots: TransformerSlots = {
     beforeImport: new Subject<BeforeImportPayload>(),
     afterImport: new Subject<AfterImportPayload>(),
@@ -366,13 +369,16 @@ export class Transformer {
     this._docCRUD = docCRUD;
 
     middlewares.forEach(middleware => {
-      middleware({
+      const cleanup = middleware({
         slots: this._slots,
         docCRUD: this._docCRUD,
         assetsManager: this._assetsManager,
         adapterConfigs: this._adapterConfigs,
         transformerConfigs: this._transformerConfigs,
       });
+      if (cleanup) {
+        this._disposables.add(cleanup);
+      }
     });
   }
 
@@ -646,4 +652,9 @@ export class Transformer {
   reset() {
     this._assetsManager.cleanup();
   }
+
+  [Symbol.dispose]() {
+    this._disposables.dispose();
+    this._assetsManager.cleanup();
+  }
 }