refactor: split project into web and server directories

- Move frontend to web/ directory
- Add server/ directory for backend
- Restructure project for前后端分离架构

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

README.md

@@ -0,0 +1,22 @@
+# X-Financial
+
+项目结构已按前后端拆开：
+
+- `web/`：前端工程（当前 Vue + Vite 项目）
+- `server/`：后端工程目录
+- `docs/`：方案和阶段文档
+- `UI/`：界面参考稿
+- `document/`：业务文档
+
+从根目录启动前端：
+
+```bash
+./start.sh
+```
+
+或手动进入前端目录：
+
+```bash
+cd web
+npm run dev
+```