refactor: 整合财务系统到主应用并重构后端架构

主要变更:
- 将独立的 web-finance 应用整合到 web-antd 主应用中
- 重命名 backend-mock 为 backend,增强后端功能
- 新增财务模块 API 端点(账户、预算、类别、交易)
- 增强财务仪表板和报表功能
- 添加 SQLite 数据存储支持和财务数据导入脚本
- 优化路由结构,删除冗余的 finance-system 模块

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

apps/backend/api/demo/bigint.ts

@@ -0,0 +1,28 @@
+export default eventHandler(async (event) => {
+  const userinfo = verifyAccessToken(event);
+  if (!userinfo) {
+    return unAuthorizedResponse(event);
+  }
+  const data = `
+  {
+    "code": 0,
+    "message": "success",
+    "data": [
+              {
+                "id": 123456789012345678901234567890123456789012345678901234567890,
+                "name": "John Doe",
+                "age": 30,
+                "email": "john-doe@demo.com"
+                },
+                {
+                "id": 987654321098765432109876543210987654321098765432109876543210,
+                "name": "Jane Smith",
+                "age": 25,
+                "email": "jane@demo.com"
+                }
+            ]
+  }
+  `;
+  setHeader(event, 'Content-Type', 'application/json');
+  return data;
+});