Fix 401 error: Add authenticated API proxy for private datasets

src/app/api/hf-proxy/route.ts

@@ -25,12 +25,16 @@ async function handleRequest(request: NextRequest, method: 'GET' | 'HEAD') {
   }
 
   // Get token from environment variable (set in Hugging Face Space secrets)
-  const token = process.env.HF_TOKEN || process.env.HUGGINGFACE_TOKEN;
+  // Hugging Face Spaces automatically inject secrets as environment variables
+  const token = process.env.HF_TOKEN || process.env.HUGGINGFACE_TOKEN || process.env.HF_API_TOKEN;
   
+  // Log token status for debugging (don't log actual token value)
   if (!token) {
-    // If no token, try without auth (for public repos)
-    // But log a warning
-    console.warn('HF_TOKEN not configured in Space secrets - requests may fail for private repos');
+    console.error('❌ HF_TOKEN not found in environment variables!');
+    console.error('Available env vars:', Object.keys(process.env).filter(k => k.includes('HF') || k.includes('TOKEN')).join(', '));
+    console.warn('⚠️  Requests to private repos will fail with 401');
+  } else {
+    console.log('✓ HF_TOKEN found in environment (length:', token.length, 'chars)');
   }
 
   try {