Use server session check for access

js/main.js

@@ -434,11 +434,16 @@ document.addEventListener('DOMContentLoaded', () => {
         return (window.matchMedia('(display-mode: standalone)').matches) || (window.navigator.standalone === true);
     }
 
-    // 조건: /findmydevice로 시작하고 access 쿠키가 없으며, PWA가 아닌 경우에만 리디렉션
-    if (location.pathname.startsWith('/findmydevice') && getCookie('access') !== '9KxH6236' && !isInStandaloneMode()) {
-        location.replace('/blog');
-        return; // 이하 코드 실행 방지
-    }
+    if (location.pathname.startsWith('/findmydevice') && !isInStandaloneMode()) {
+        fetch('/custom/launcher/api.php?session=1', { credentials: 'same-origin' })
+            .then(res => res.ok ? res.json() : Promise.reject())
+            .then(session => {
+                if (!session.authenticated) {
+                    location.replace('/blog');
+                }
+            })
+            .catch(() => location.replace('/blog'));
+    }
 
     const btnArea = document.querySelector('body > div.btnArea');
     const pageModifyLink = btnArea?.querySelectorAll('a')[1]?.getAttribute('href') || '';