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/shared/src/adapters/utils/file-path.ts

@@ -0,0 +1,56 @@
+/**
+ * Normalizes a relative path by resolving all relative path segments
+ * @param basePath The base path (markdown file's directory)
+ * @param relativePath The relative path to normalize
+ * @returns The full path
+ */
+function resolveFullPath(basePath: string, relativePath: string): string {
+  // Split both paths into segments
+  const baseSegments = basePath.split('/').filter(Boolean);
+  const relativeSegments = relativePath.split('/').filter(Boolean);
+
+  // Handle each segment of the relative path
+  for (const segment of relativeSegments) {
+    if (segment === '.') {
+      // Current directory, do nothing
+      continue;
+    } else if (segment === '..') {
+      // Parent directory, remove last segment from base
+      if (baseSegments.length > 0) {
+        baseSegments.pop();
+      }
+    } else {
+      // Regular directory or file, add to base
+      baseSegments.push(segment);
+    }
+  }
+
+  // Join segments back into a path
+  return baseSegments.join('/');
+}
+
+/**
+ * Get the full path of the reference image from the file path and the image reference
+ * @param filePath The full path of the file containing the image reference
+ * @param imageReference The image reference from the file (can be relative or absolute path)
+ * @returns The full path of the reference image
+ */
+export function getImageFullPath(
+  filePath: string,
+  imageReference: string
+): string {
+  // Decode the image reference in case it contains URL-encoded characters
+  const decodedReference = decodeURIComponent(imageReference);
+
+  // Get the directory of the file path
+  const markdownDir = filePath.substring(0, filePath.lastIndexOf('/'));
+
+  // Check if the image reference is a relative path
+  const isRelative = !decodedReference.startsWith('/');
+
+  // If the image reference is a relative path, resolve it against the file path's directory
+  // Otherwise, it is an absolute path, remove the leading slash if it exists
+  return isRelative
+    ? resolveFullPath(markdownDir, decodedReference)
+    : decodedReference.replace(/^\//, '');
+}

blocksuite/affine/shared/src/adapters/utils/index.ts

@@ -1,3 +1,4 @@
 export * from './fetch.js';
+export * from './file-path.js';
 export * from './hast.js';
 export * from './text.js';