feat: 添加用户认证组件

- LoginPage（登录页）
- RegisterPage（注册页）
- 更新 App.js 路由配置
- 集成 AuthStore

frontend/src/App.js

@@ -10,6 +10,8 @@ import CitiesPage from './components/region/CitiesPage';
 import CityDetailPage from './components/region/CityDetailPage';
 import ArticleDetailPage from './components/article/ArticleDetailPage';
 import ServiceDetailPage from './components/service/ServiceDetailPage';
+import LoginPage from './components/auth/LoginPage';
+import RegisterPage from './components/auth/RegisterPage';
 
 const Container = styled.div`
   max-width: 1200px;
@@ -46,6 +48,8 @@ function App() {
         <Route path="/cities/:regionId" element={<CityDetailPage />} />
         <Route path="/articles/:articleId" element={<ArticleDetailPageWrapper />} />
         <Route path="/services/:serviceId" element={<ServiceDetailPageWrapper />} />
+        <Route path="/login" element={<LoginPage />} />
+        <Route path="/register" element={<RegisterPage />} />
         <Route path="/user/profile" element={<UserProfilePage />} />
         <Route path="*" element={<NotFoundPage />} />
       </Routes>