feat(client): add auth logic

client/src/App.tsx

@@ -1,10 +1,21 @@
-import React from 'react';
+/* eslint-disable react-hooks/exhaustive-deps */
+import React, { useEffect } from 'react';
 import { Route, Routes } from 'react-router-dom';
 import MainLayout from './pages/MainLayout';
 import ProtectedRoute from './pages/ProtectedRoute';
 import LoginPage from './pages/LoginPage';
+import { useSetUserSelector } from './store/userStore';
 
 function App() {
+  const setUser = useSetUserSelector();
+
+  useEffect(() => {
+    const storedUser = localStorage.getItem('user');
+    if (storedUser) {
+      setUser(JSON.parse(storedUser));
+    }
+  }, []);
+
   return (
     <div className="App">
       <Routes>