i18n: translate frontend UI strings to English

src/pages/NotificationsPage.tsx

@@ -32,16 +32,16 @@ export default function NotificationsPage() {
   return (
     <div className="notifications-page">
       <div className="page-header">
-        <h2>🔔 通知 {unreadCount > 0 && <span className="badge" style={{ background: 'var(--danger)' }}>{unreadCount}</span>}</h2>
+        <h2>🔔 Notifications {unreadCount > 0 && <span className="badge" style={{ background: 'var(--danger)' }}>{unreadCount}</span>}</h2>
         {unreadCount > 0 && (
-          <button className="btn-primary" onClick={markAllRead}>全部标记已读</button>
+          <button className="btn-primary" onClick={markAllRead}>Mark all read</button>
         )}
       </div>
 
       <div className="filters">
         <label className="filter-check">
           <input type="checkbox" checked={unreadOnly} onChange={(e) => setUnreadOnly(e.target.checked)} />
-          仅显示未读
+          Show unread only
         </label>
       </div>
 
@@ -62,7 +62,7 @@ export default function NotificationsPage() {
             </div>
           </div>
         ))}
-        {notifications.length === 0 && <p className="empty">暂无通知</p>}
+        {notifications.length === 0 && <p className="empty">No notifications</p>}
       </div>
     </div>
   )