Fix router guard broken cookie check to use isLuciaLoggedIn cookie

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/router/index.ts

@@ -162,12 +162,12 @@ const router = createRouter({
 router.beforeEach((to, from) => {
   // to: Route: 即將要進入的目標 路由物件
   // from: Route: 當前導航正要離開的路由
-  let isRemoveCookie = document.cookie.split(';').some(c => c.trim().startsWith('expires=Thu, 01 Jan 1970 00:00:00 UTC;')); // 是否登入，有到期日表示已登出。
 
-  // 當路由到 login 時，有登入要跳轉至home
+  // 當路由到 login 時，已登入則跳轉至 Files
   if (to.name === 'Login') {
-   if (isRemoveCookie) router.push({ name: 'Files' });
+    const isLoggedIn = document.cookie.split(';').some(c => c.trim().startsWith('isLuciaLoggedIn='));
+    if (isLoggedIn) return { name: 'Files' };
   }
- });
+});
 
 export default router;