Fix black screen: wait for Vite before Electron, retry loadURL, show boot fallback.

Co-authored-by: Cursor <cursoragent@cursor.com>

app/renderer/App.tsx

@@ -155,12 +155,22 @@ export function App() {
     void (async () => {
       if (!window.ttrpgBuilder) {
         setBooting(false);
+        setStatus(
+          locale === 'ru'
+            ? 'Нет связи с Electron preload (перезапустите npm run dev)'
+            : 'Electron preload missing (restart npm run dev)',
+        );
         return;
       }
-      await window.ttrpgBuilder.seedPresets();
-      await refresh();
-      setBooting(false);
-      setStatus(locale === 'ru' ? 'Пресеты готовы' : 'Presets ready');
+      try {
+        await window.ttrpgBuilder.seedPresets();
+        await refresh();
+        setStatus(locale === 'ru' ? 'Пресеты готовы' : 'Presets ready');
+      } catch (e) {
+        setStatus(String(e));
+      } finally {
+        setBooting(false);
+      }
     })();
   }, [refresh, locale]);
 

app/renderer/index.html

@@ -4,9 +4,13 @@
     <meta charset="UTF-8" />
     <meta name="viewport" content="width=device-width, initial-scale=1.0" />
     <title>TTRPG Character Builder</title>
+    <style>
+      html, body { margin: 0; height: 100%; background: #09090b; color: #eee; font-family: Segoe UI, sans-serif; }
+      #boot-fallback { padding: 24px; }
+    </style>
   </head>
   <body>
-    <div id="root"></div>
+    <div id="root"><div id="boot-fallback">Loading TTRPG Character Builder…</div></div>
     <script type="module" src="./main.tsx"></script>
   </body>
 </html>

app/renderer/main.tsx

@@ -2,4 +2,21 @@ import { createRoot } from 'react-dom/client';
 import { App } from './App.tsx';
 import './styles.css';
 
-createRoot(document.getElementById('root')!).render(<App />);
+const rootEl = document.getElementById('root');
+if (!rootEl) {
+  document.body.innerHTML = '<pre style="color:#f66;padding:24px">#root missing</pre>';
+} else {
+  try {
+    createRoot(rootEl).render(<App />);
+  } catch (err) {
+    rootEl.innerHTML = `<pre style="color:#f66;padding:24px;white-space:pre-wrap">${String(err)}</pre>`;
+    console.error(err);
+  }
+}
+
+window.addEventListener('error', (e) => {
+  console.error('window.error', e.error || e.message);
+});
+window.addEventListener('unhandledrejection', (e) => {
+  console.error('unhandledrejection', e.reason);
+});