feat: implement image proxy for YouTube CDN images with caching to prevent rate limits

client/lib/imageProxy.ts

@@ -0,0 +1,27 @@
+const BACKEND_URL = process.env.NEXT_PUBLIC_BACKEND_URL ?? 'http://localhost:4100';
+
+/**
+ * Converts a YouTube CDN image URL to use our backend proxy
+ * This prevents 429 rate limit errors from YouTube's CDN
+ */
+export function proxyImageUrl(url: string | undefined): string | undefined {
+  if (!url) return undefined;
+  
+  // Check if it's a YouTube CDN URL
+  const youtubeCdnDomains = ['yt3.ggpht.com', 'yt4.ggpht.com', 'i.ytimg.com'];
+  
+  try {
+    const urlObj = new URL(url);
+    if (youtubeCdnDomains.includes(urlObj.hostname)) {
+      // Proxy through our backend
+      return `${BACKEND_URL}/proxy/image?url=${encodeURIComponent(url)}`;
+    }
+  } catch {
+    // If URL parsing fails, return as-is
+    return url;
+  }
+  
+  // Return non-YouTube URLs as-is
+  return url;
+}
+