fix(ui): show loading state during token authentication

src/app/auth/token/login/page.tsx

@@ -46,7 +46,14 @@ function TokenLoginContent() {
       });
   }, [searchParams, router, setAuthData]);
 
-  return null;
+  return (
+    <div className="min-h-screen flex items-center justify-center bg-gray-900">
+      <div className="text-center">
+        <div className="animate-spin rounded-full h-12 w-12 border-b-2 border-orange-500 mx-auto mb-4"></div>
+        <p className="text-gray-400 text-sm">Authenticating...</p>
+      </div>
+    </div>
+  );
 }
 
 export default function TokenLoginPage() {