feat: 添加前端页面和业务说明书

refactor(server): 重构服务层代码结构
feat(server): 添加基础设施、跨境电商、AI决策等核心服务
docs: 完善前端业务说明书和开发进度文档
style: 格式化代码和文档

dashboard/src/pages/Merchant/index.tsx

@@ -0,0 +1,29 @@
+import React from 'react';
+import { Card, Layout, Typography, Row, Col, Button } from 'antd';
+import { UserOutlined, PlusOutlined } from '@ant-design/icons';
+
+const { Content } = Layout;
+const { Title, Text } = Typography;
+
+const MerchantManagement: React.FC = () => {
+  return (
+    <Content style={{ padding: 24, margin: 0, minHeight: 280, background: '#fff' }}>
+      <div style={{ display: 'flex', justifyContent: 'space-between', alignItems: 'center', marginBottom: 24 }}>
+        <Title level={4}>商户管理</Title>
+        <Button type="primary" icon={<PlusOutlined />}>
+          添加商户
+        </Button>
+      </div>
+      
+      <Row gutter={[16, 16]}>
+        <Col span={24}>
+          <Card title="商户列表">
+            <Text>商户管理页面内容</Text>
+          </Card>
+        </Col>
+      </Row>
+    </Content>
+  );
+};
+
+export default MerchantManagement;