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/package.json

@@ -0,0 +1,23 @@
+{
+  "name": "@vben/backend",
+  "version": "0.0.1",
+  "description": "",
+  "private": true,
+  "license": "MIT",
+  "author": "",
+  "scripts": {
+    "build": "nitro build",
+    "start": "nitro dev",
+    "import:data": "node scripts/import-finance-data.js"
+  },
+  "dependencies": {
+    "@faker-js/faker": "catalog:",
+    "better-sqlite3": "9.5.0",
+    "jsonwebtoken": "catalog:",
+    "nitropack": "catalog:"
+  },
+  "devDependencies": {
+    "@types/jsonwebtoken": "catalog:",
+    "h3": "catalog:"
+  }
+}