Fix: Resilient boot with localStorage error handling

src/main.js

@@ -166,7 +166,20 @@ function boot() {
   el.setupSave?.addEventListener('click', () => {
     const key = (el.setupKey?.value || '').trim();
     if (!key) return;
-    setApiKey(key);
+    try {
+      setApiKey(key);
+    } catch (e) {
+      console.warn('localStorage write failed, clearing and retrying:', e);
+      try {
+        localStorage.removeItem('vibegif_api_key');
+        localStorage.clear();
+        setApiKey(key);
+      } catch (e2) {
+        console.error('localStorage completely broken:', e2);
+        alert('Could not save API key — localStorage may be full or blocked. Try clearing site data.');
+        return;
+      }
+    }
     if (el.setupKey) el.setupKey.value = '';
     showMain();
   });