refactor: 불필요한 디버깅용 코드 삭제

Author: YeBeenChoi

src/app/layout/MainLayout.tsx

@@ -1,24 +1,10 @@
 import { Header } from '@shared/ui/Header';
-import { useEffect, useState } from 'react';
 import { Outlet } from 'react-router';
 
 export default function MainLayout() {
-  const [isLoggedIn, setIsLoggedIn] = useState(false);
-
-  useEffect(() => {
-    if (typeof window === 'undefined') {
-      return;
-    }
-
-    setIsLoggedIn(Boolean(window.localStorage.getItem('loopit:isLoggedIn')));
-  }, []);
-
   return (
     <div className="min-h-screen bg-white">
-      <Header
-        isLoggedIn={isLoggedIn}
-        user={isLoggedIn ? { profileImage: '/profile-sample.jpg', nickname: '루핏' } : undefined}
-      />
+      <Header />
       <Outlet />
     </div>
   );