chore: proxy image preview in frontend (#11957)

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

- **New Features**
	- Images and icons in bookmark cards are now loaded through an image proxy for improved reliability and consistency.
	- Embed blocks for GitHub, Loom, and YouTube now display banner and creator images via an image proxy service for enhanced image loading.

- **Refactor**
	- Simplified backend URL handling and proxy logic for images, resulting in more efficient processing and reduced complexity.
	- Consolidated image proxy middleware and services into a shared adapter module for streamlined imports and improved maintainability.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

packages/backend/server/src/plugins/worker/controller.ts

@@ -209,7 +209,6 @@ export class WorkerController {
         videos: [],
         favicons: [],
       };
-      const baseUrl = new URL(request.url, this.url.baseUrl).toString();
 
       if (response.body) {
         const resp = await decodeWithCharset(response, res);
@@ -276,7 +275,7 @@ export class WorkerController {
 
         await rewriter.transform(resp).text();
 
-        res.images = await reduceUrls(baseUrl, res.images);
+        res.images = await reduceUrls(res.images);
 
         this.logger.debug('Processed response with HTMLRewriter', {
           origin,
@@ -293,7 +292,7 @@ export class WorkerController {
           appendUrl(faviconUrl.toString(), res.favicons);
         }
 
-        res.favicons = await reduceUrls(baseUrl, res.favicons);
+        res.favicons = await reduceUrls(res.favicons);
       }
 
       const json = JSON.stringify(res);