Fix: Express 5 requirement for named parameters in catch-all route

backend/server.js

@@ -134,7 +134,7 @@ app.get('/manifesto', (req, res) => res.sendFile(path.join(__dirname, 'public',
 app.get('/broadcast', (req, res) => res.sendFile(path.join(__dirname, 'public', 'broadcast.html')));
 
 // Catch-all for React/Frontend routes should come AFTER specific API/Static routes
-app.get('(.*)', (req, res, next) => {
+app.get('/:path*', (req, res, next) => {
   if (req.path.startsWith('/api')) return next();
   res.sendFile(path.join(__dirname, 'public', 'index.html'));
 });