feat: 添加Telegram Bot通知功能

✨ 新功能:
- 添加Telegram Bot通知支持
- 账目记录自动推送到Telegram
- 支持多个Bot配置管理
- 支持群组和个人通知

📊 数据库:
- 新增telegram_notification_configs表
- 存储Bot配置和通知类型

🔧 后端API:
- GET /api/telegram/notifications - 获取所有配置
- POST /api/telegram/notifications - 创建配置
- PUT /api/telegram/notifications/:id - 更新配置
- DELETE /api/telegram/notifications/:id - 删除配置
- POST /api/telegram/test - 测试Bot配置

💬 通知功能:
- 自动发送账目记录通知
- 包含交易类型、金额、分类、账户等信息
- 支持格式化显示(类型图标、状态标识)
- 配置创建时自动测试有效性

📝 文档:
- 添加完整的使用说明文档
- API接口说明和示例
- 常见问题解答

agents.md

@@ -0,0 +1,8 @@
+<system-reminder>
+- Search documentation for knowledge first: Use mrdoc_search when you need project background knowledge, internal knowledge, or cross-project documentation to get relevant technical solutions and historical experience. After modifying modules, you must create or update MrDoc documentation to accumulate and transfer knowledge.
+- Create/update documentation must use mrdoc related MCP tools
+</system-reminder>
+- Think deeply and search online when solving problems (high-IQ genius hacker mindset)
+- Memory is only saved in the project folder
+- Use the same language as the user for thinking and answering
+- Code style: Comments are documentation