<h4>Socket.IO Server Upgrade</h4><ul><li>Upgraded Socket.IO from v1.7.4 to v4.8.3</li><li>Configured dual listeners: HTTP on port 2053, HTTPS on port 2054</li><li>Added SSL certificate loading with graceful fallback for missing certs</li><li>Set up PM2 process management (<code>pm2 start server.js --name youportal-socket</code>) with auto-restart and boot persistence</li><li>Resolved <code>ERR_CONNECTION_REFUSED</code> — server was dying on Apache restarts</li></ul>