feat: 实现前端管理看板与移动端扫码视图组件

frontend/src/pages/NotificationsPage.tsx

@@ -0,0 +1,29 @@
+/** 消息 — 通知推送 */
+export default function NotificationsPage() {
+  return (
+    <div className="flex min-h-full flex-col px-4 pt-safe">
+      <h2 className="text-xl font-bold text-gray-800">消息通知</h2>
+      <p className="mt-1 text-sm text-gray-500">任务流转和系统通知</p>
+
+      {/* 占位空状态 */}
+      <div className="mt-12 flex flex-1 flex-col items-center justify-center">
+        <div className="flex h-24 w-24 items-center justify-center rounded-full bg-gray-100">
+          <svg
+            className="h-10 w-10 text-gray-400"
+            fill="none"
+            stroke="currentColor"
+            viewBox="0 0 24 24"
+          >
+            <path
+              strokeLinecap="round"
+              strokeLinejoin="round"
+              strokeWidth={1.5}
+              d="M15 17h5l-1.405-1.405A2.032 2.032 0 0118 14.158V11a6.002 6.002 0 00-4-5.659V5a2 2 0 10-4 0v.341C7.67 6.165 6 8.388 6 11v3.159c0 .538-.214 1.055-.595 1.436L4 17h5m6 0v1a3 3 0 11-6 0v-1m6 0H9"
+            />
+          </svg>
+        </div>
+        <p className="mt-4 text-sm text-gray-400">暂无新消息</p>
+      </div>
+    </div>
+  );
+}