Refactor image URL handling: Update API routes to return image URLs via the API instead of direct paths, ensuring consistency across avatar and background uploads. Introduce normalization functions for avatar and background URLs to maintain compatibility with existing URLs.

app/api/admin/images/list/route.ts

@@ -26,7 +26,7 @@ export async function GET() {
         (file) =>
           file.match(/\.(jpg|jpeg|png|gif|webp|svg)$/i) && !file.startsWith(".")
       );
-      images.push(...imageFiles.map((file) => `/uploads/backgrounds/${file}`));
+      images.push(...imageFiles.map((file) => `/api/backgrounds/${file}`));
     }
 
     return NextResponse.json({ images });