feat(core): import progress & perf (#15197)

#### PR Dependency Tree


* **PR #15197** 👈

This tree was auto-generated by
[Charcoal](https://github.com/danerwilliams/charcoal)

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

* **New Features**
* Added a new import pipeline with “plan then commit” batch handling for
Markdown, Notion HTML, Obsidian, and Bear backups.
* Enabled native import sessions with progress, cancellation, and
batch-by-batch committing (including assets, folders, icons, and tags).
  * Added web preflight limits for ZIP and multi-file imports.
* **Bug Fixes**
* Improved import error/warning reporting and continued processing when
some items fail.
* Strengthened snapshot-based file/directory picking to preserve paths.
* **Chores**
  * Updated project packaging/configuration for the new import workflow.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

blocksuite/playground/apps/_common/components/starter-debug-menu.ts

@@ -54,6 +54,7 @@ import {
   type Workspace,
 } from '@blocksuite/affine/store';
 import {
+  commitImportBatchToWorkspace,
   createAssetsArchive,
   download,
   HtmlTransformer,
@@ -436,12 +437,17 @@ export class StarterDebugMenu extends ShadowlessElement {
     try {
       const file = await openSingleFileWith('Zip');
       if (!file) return;
-      const { docIds } = await MarkdownTransformer.importMarkdownZip({
+      const { batch } = await MarkdownTransformer.planMarkdownZip({
         collection: this.collection,
         schema: this.editor.doc.schema,
         imported: file,
         extensions: this._getStoreManager().get('store'),
       });
+      const { docIds } = await commitImportBatchToWorkspace(
+        this.collection,
+        this.editor.doc.schema,
+        batch
+      );
       if (!this.editor.host) return;
       toast(
         this.editor.host,
@@ -473,16 +479,21 @@ export class StarterDebugMenu extends ShadowlessElement {
     try {
       const file = await openSingleFileWith('Zip');
       if (!file) return;
-      const result = await NotionHtmlTransformer.importNotionZip({
+      const { batch } = await NotionHtmlTransformer.planNotionHtmlZip({
         collection: this.collection,
         schema: this.editor.doc.schema,
         imported: file,
         extensions: this._getStoreManager().get('store'),
       });
+      const result = await commitImportBatchToWorkspace(
+        this.collection,
+        this.editor.doc.schema,
+        batch
+      );
       if (!this.editor.host) return;
       toast(
         this.editor.host,
-        `Successfully imported ${result.pageIds.length} Notion HTML pages.`
+        `Successfully imported ${result.docIds.length} Notion HTML pages.`
       );
     } catch (error) {
       console.error('Failed to import Notion HTML Zip:', error);