Serve thumbnails directly from the CDN for better performance and reliability

Removes thumbnail proxy and updates `BunnyService` to use CDN URL for thumbnails.

Replit-Commit-Author: Agent
Replit-Commit-Session-Id: aa92e7e2-ec62-4c92-b21b-02ef78a664c2
Replit-Commit-Checkpoint-Type: full_checkpoint
Replit-Commit-Screenshot-Url: https://storage.googleapis.com/screenshot-production-us-central1/8cc42625-c1f5-4e43-99bd-77f2c4dedee2/aa92e7e2-ec62-4c92-b21b-02ef78a664c2/rF0yTnz

server/bunny.ts

@@ -52,8 +52,9 @@ export class BunnyService {
   }
 
   private bunnyVideoToVideo(bunnyVideo: BunnyVideo): Video {
-    // Use server-side proxy for thumbnails since they are private
-    const thumbnailUrl = `/thumbnail/${bunnyVideo.guid}`;
+    // For private videos, use iframe embed or proxy approach
+    // Generate thumbnail URL from CDN (thumbnails are usually public)
+    const thumbnailUrl = `https://${this.hostname}/${bunnyVideo.guid}/thumbnail.jpg`;
 
     // For private videos, we'll use an iframe embed URL which handles authentication
     const videoUrl = `https://iframe.mediadelivery.net/embed/${this.libraryId}/${bunnyVideo.guid}`;