fix(editor): support relative image reference path when importing zip with images (#12264)

Closes: [BS-3385](https://linear.app/affine-design/issue/BS-3385/markdown类型的导入，支持media文件和md文件不在同目录的情况)

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

- **New Features**
  - Added utility functions to resolve and normalize image file paths in markdown and HTML imports.
  - Introduced middleware to provide full file path context during file import and transformation.
  - Added new types for improved asset and file management in zip imports.

- **Refactor**
  - Centralized and simplified image processing logic across HTML, Markdown, and Notion HTML adapters for improved maintainability.
  - Enhanced type safety and clarity in file and asset handling during zip imports.

- **Tests**
  - Added comprehensive tests for image file path resolution utility.

- **Documentation**
  - Improved inline code comments explaining file path resolution logic.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

blocksuite/affine/widgets/linked-doc/src/transformers/markdown.ts

@@ -2,6 +2,7 @@ import {
   defaultImageProxyMiddleware,
   docLinkBaseURLMiddleware,
   fileNameMiddleware,
+  filePathMiddleware,
   MarkdownAdapter,
   titleMiddleware,
 } from '@blocksuite/affine-shared/adapters';
@@ -16,6 +17,7 @@ import type {
 } from '@blocksuite/store';
 import { extMimeMap, Transformer } from '@blocksuite/store';
 
+import type { AssetMap, ImportedFileEntry, PathBlobIdMap } from './type.js';
 import { createAssetsArchive, download, Unzip } from './utils.js';
 
 function getProvider(extensions: ExtensionType[]) {
@@ -196,19 +198,28 @@ async function importMarkdownZip({
   await unzip.load(imported);
 
   const docIds: string[] = [];
-  const pendingAssets = new Map<string, File>();
-  const pendingPathBlobIdMap = new Map<string, string>();
-  const markdownBlobs: [string, Blob][] = [];
+  const pendingAssets: AssetMap = new Map();
+  const pendingPathBlobIdMap: PathBlobIdMap = new Map();
+  const markdownBlobs: ImportedFileEntry[] = [];
 
+  // Iterate over all files in the zip
   for (const { path, content: blob } of unzip) {
+    // Skip the files that are not markdown files
     if (path.includes('__MACOSX') || path.includes('.DS_Store')) {
       continue;
     }
 
+    // Get the file name
     const fileName = path.split('/').pop() ?? '';
+    // If the file is a markdown file, store it to markdownBlobs
     if (fileName.endsWith('.md')) {
-      markdownBlobs.push([fileName, blob]);
+      markdownBlobs.push({
+        filename: fileName,
+        contentBlob: blob,
+        fullPath: path,
+      });
     } else {
+      // If the file is not a markdown file, store it to pendingAssets
       const ext = path.split('.').at(-1) ?? '';
       const mime = extMimeMap.get(ext) ?? '';
       const key = await sha(await blob.arrayBuffer());
@@ -218,8 +229,9 @@ async function importMarkdownZip({
   }
 
   await Promise.all(
-    markdownBlobs.map(async ([fileName, blob]) => {
-      const fileNameWithoutExt = fileName.replace(/\.[^/.]+$/, '');
+    markdownBlobs.map(async markdownFile => {
+      const { filename, contentBlob, fullPath } = markdownFile;
+      const fileNameWithoutExt = filename.replace(/\.[^/.]+$/, '');
       const job = new Transformer({
         schema,
         blobCRUD: collection.blobSync,
@@ -232,18 +244,25 @@ async function importMarkdownZip({
           defaultImageProxyMiddleware,
           fileNameMiddleware(fileNameWithoutExt),
           docLinkBaseURLMiddleware(collection.id),
+          filePathMiddleware(fullPath),
         ],
       });
       const assets = job.assets;
       const pathBlobIdMap = job.assetsManager.getPathBlobIdMap();
-      for (const [key, value] of pendingAssets.entries()) {
-        assets.set(key, value);
-      }
-      for (const [key, value] of pendingPathBlobIdMap.entries()) {
-        pathBlobIdMap.set(key, value);
+      // Iterate over all assets to be imported
+      for (const [assetPath, key] of pendingPathBlobIdMap.entries()) {
+        // Get the relative path of the asset to the markdown file
+        // Store the path to blobId map
+        pathBlobIdMap.set(assetPath, key);
+        // Store the asset to assets, the key is the blobId, the value is the file object
+        // In block adapter, it will use the blobId to get the file object
+        if (pendingAssets.get(key)) {
+          assets.set(key, pendingAssets.get(key)!);
+        }
       }
+
       const mdAdapter = new MarkdownAdapter(job, provider);
-      const markdown = await blob.text();
+      const markdown = await contentBlob.text();
       const doc = await mdAdapter.toDoc({
         file: markdown,
         assets: job.assetsManager,