Improve gallery loading speed with image optimization and lazy loading

Implement a thumbnail proxy endpoint and lazy loading for gallery images to significantly reduce page load times and improve user experience.

Replit-Commit-Author: Agent
Replit-Commit-Session-Id: 517dfa7b-26ac-463d-a6e1-a58c6df97188
Replit-Commit-Checkpoint-Type: full_checkpoint
Replit-Commit-Event-Id: 1488855f-6772-48e1-9244-282d1cc91352
Replit-Commit-Screenshot-Url: https://storage.googleapis.com/screenshot-production-us-central1/f209e72a-0939-48fa-84fc-57854de71967/517dfa7b-26ac-463d-a6e1-a58c6df97188/VgutZ7W
Replit-Helium-Checkpoint-Created: true

server/dropbox.ts

@@ -114,7 +114,7 @@ async function refreshAccessToken(refreshToken: string): Promise<DropboxTokens>
   return tokens;
 }
 
-async function getValidAccessToken(): Promise<string | null> {
+export async function getValidAccessToken(): Promise<string | null> {
   let tokens = loadTokens();
   if (!tokens) return null;
 
@@ -200,6 +200,7 @@ async function getTemporaryLinks(accessToken: string, paths: string[]): Promise<
   return results;
 }
 
+
 const galleryCache: { data: GalleryImage[]; timestamp: number } = { data: [], timestamp: 0 };
 const CACHE_DURATION = 30 * 60 * 1000;