Initial TTRPG character meta-builder with visual sheet editor.

Offline Electron app seeds 10 system presets, supports create-from-scratch designer with palette/drag/resize/bricks, and exports .ttrpg-system.json for the player.

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

app/renderer/main.tsx

@@ -0,0 +1,5 @@
+import { createRoot } from 'react-dom/client';
+import { App } from './App.tsx';
+import './styles.css';
+
+createRoot(document.getElementById('root')!).render(<App />);