feat: login page, 401 interceptor, nav sign-out

frontend/src/api/index.ts

@@ -10,6 +10,16 @@ const api = axios.create({
   withCredentials: true,
 })
 
+api.interceptors.response.use(
+  response => response,
+  error => {
+    if (error.response?.status === 401 && window.location.pathname !== '/login') {
+      window.location.href = '/login'
+    }
+    return Promise.reject(error)
+  }
+)
+
 export const mealPlannerApi = {
   auth: {
     login: (password: string) => api.post('/auth/login', { password }),