fix: update Socket.IO connection to use dynamic host from environment variable

app/event/[id]/page.tsx

@@ -67,7 +67,8 @@ export default function EventPage() {
       .then(({ io }) => {
         if (!mounted) return;
         const socketPort = process.env.NEXT_PUBLIC_SOCKET_PORT || "4000";
-        const socket = io(`http://10.20.0.188:${socketPort}`, {
+        const socketHost = process.env.NEXT_PUBLIC_SOCKET_HOST || window.location.hostname;
+        const socket = io(`http://${socketHost}:${socketPort}`, {
           autoConnect: true 
         });
         socketRef.current = socket;