Huge update.

resource/static/js/home.js

@@ -0,0 +1,33 @@
+let pendingUsername = null;
+
+function getUsername() {
+    const username = document.getElementById('username-input').value.trim();
+    if (!username) {
+        alert("Please enter your name.");
+        throw new Error("Username required");
+    }
+    pendingUsername = username;
+    return username;
+}
+
+document.getElementById('create-button').addEventListener('click', async () => {
+    try {
+        const username = getUsername();
+        const res = await fetch('/api/room', {
+            method: 'POST',
+            headers: { 'Content-Type': 'application/json' },
+            body: JSON.stringify({})
+        });
+        const data = await res.json();
+        if (data.code) {
+            const allUsernames = JSON.parse(localStorage.getItem('usernames') || '{}');
+            allUsernames[data.code] = pendingUsername;
+            localStorage.setItem('usernames', JSON.stringify(allUsernames));
+            
+            window.location.href = `/room/${data.code}`;
+        } else {
+            alert("Failed to create room.");
+        }
+    } catch (_) {
+    }
+});