Update app.js

app.js

@@ -133,4 +133,4 @@ wss.on('connection', ws => {
 });
 
 const PORT = process.env.PORT || 7860;
-server.listen(PORT, () => console.log(\`✅ Activity server running at http://localhost:\${PORT}/\`));
+server.listen(PORT, () => console.log(`✅ Activity server running at http://localhost:${PORT}`));