perf: preload stargazer avatars for instant Stargazers panel

docs/app/dashboard/page.tsx

@@ -25,6 +25,23 @@ export default function DashboardPage() {
   const { refresh, ...stats } = useGitHubStats();
   const [showStargazers, setShowStargazers] = useState(false);
 
+  // Preload stargazer avatar images in background so the panel opens instantly
+  useEffect(() => {
+    if (!stats.stargazers || stats.stargazers.length === 0) return;
+    const head = document.head || document.getElementsByTagName('head')[0];
+    const existing = new Set(Array.from(head.querySelectorAll('link[rel="preload"][as="image"]')).map((l) => (l as HTMLLinkElement).href));
+
+    stats.stargazers.slice(0, 100).forEach((s) => {
+      const url = s.avatarUrl + '&s=128';
+      if (existing.has(url)) return;
+      const link = document.createElement('link');
+      link.rel = 'preload';
+      link.as = 'image';
+      link.href = url;
+      head.appendChild(link);
+    });
+  }, [stats.stargazers]);
+
   const toggleStargazers = useCallback(() => setShowStargazers((prev) => !prev), []);
   const closeStargazers = useCallback(() => setShowStargazers(false), []);