feat: add secure login page with jwt authentication and button animation

src/dataService.ts

@@ -2,9 +2,49 @@ import type { OrderData } from './types';
 
 const API_URL = import.meta.env.VITE_API_URL || '/api';
 
+export const login = async (email: string, password: string): Promise<boolean> => {
+  try {
+    const response = await fetch(`${API_URL}/login`, {
+      method: 'POST',
+      headers: {
+        'Content-Type': 'application/json',
+      },
+      body: JSON.stringify({ email, password }),
+    });
+
+    if (response.ok) {
+      const data = await response.json();
+      localStorage.setItem('auth_token', data.token);
+      return true;
+    }
+    return false;
+  } catch (error) {
+    console.error('Login failed', error);
+    return false;
+  }
+};
+
+export const logout = () => {
+  localStorage.removeItem('auth_token');
+  window.location.href = '/#/login';
+};
+
+export const isAuthenticated = (): boolean => {
+  return !!localStorage.getItem('auth_token');
+};
+
 export const fetchData = async (): Promise<OrderData[]> => {
     try {
-        const response = await fetch(`${API_URL}/data`);
+        const token = localStorage.getItem('auth_token');
+        const response = await fetch(`${API_URL}/data`, {
+            headers: {
+                'Authorization': `Bearer ${token}`
+            }
+        });
+        if (response.status === 401 || response.status === 403) {
+            logout();
+            return [];
+        }
         if (!response.ok) return [];
         return await response.json();
     } catch (error) {