feat: Airwallex 发卡管理后台完整实现

- 后端: FastAPI + SQLAlchemy + SQLite, JWT认证, 代理支持的AirwallexClient
- 前端: React 18 + Vite + Ant Design 5, 中文界面
- 功能: 卡片管理, 持卡人管理, 交易记录, API令牌, 系统设置, 审计日志
- 第三方API: X-API-Key认证, 权限控制
- Docker部署: docker-compose编排前后端

frontend/src/pages/Login.tsx

@@ -0,0 +1,51 @@
+import { useState } from 'react'
+import { useNavigate } from 'react-router-dom'
+import { Card, Form, Input, Button, message } from 'antd'
+import { UserOutlined, LockOutlined, CreditCardOutlined } from '@ant-design/icons'
+import { useAuthStore } from '@/stores/auth'
+
+export default function Login() {
+  const [loading, setLoading] = useState(false)
+  const login = useAuthStore((s) => s.login)
+  const navigate = useNavigate()
+
+  const onFinish = async (values: { username: string; password: string }) => {
+    setLoading(true)
+    try {
+      await login(values.username, values.password)
+      message.success('登录成功')
+      navigate('/')
+    } catch (err: unknown) {
+      const error = err as { response?: { data?: { detail?: string } } }
+      message.error(error.response?.data?.detail || '登录失败，请检查用户名和密码')
+    } finally {
+      setLoading(false)
+    }
+  }
+
+  return (
+    <div className="login-container">
+      <Card className="login-card">
+        <div style={{ textAlign: 'center', marginBottom: 32 }}>
+          <CreditCardOutlined style={{ fontSize: 48, color: '#667eea' }} />
+          <h2 className="login-title" style={{ marginTop: 12 }}>
+            Airwallex 发卡管理系统
+          </h2>
+        </div>
+        <Form name="login" onFinish={onFinish} size="large" autoComplete="off">
+          <Form.Item name="username" rules={[{ required: true, message: '请输入用户名' }]}>
+            <Input prefix={<UserOutlined />} placeholder="用户名" />
+          </Form.Item>
+          <Form.Item name="password" rules={[{ required: true, message: '请输入密码' }]}>
+            <Input.Password prefix={<LockOutlined />} placeholder="密码" />
+          </Form.Item>
+          <Form.Item>
+            <Button type="primary" htmlType="submit" loading={loading} block>
+              登录
+            </Button>
+          </Form.Item>
+        </Form>
+      </Card>
+    </div>
+  )
+}