feat(monitor): 添加任务管理模块

- 在 README 中添加了 Celery 任务管理的说明
- 在系统菜单中添加了任务管理相关菜单项
- 添加了任务管理的路由和权限
- 引入了 croniter 库用于处理 cron 表达式

README.en.md

@@ -152,6 +152,9 @@ git clone https://gitee.com/tao__tao/fastapi_vue3_admin.git
    ```shell
    # Run in the root directory of the backend project (backend)
    python3 main.py run
+   # If using Celery to manage tasks, you need to start Celery separately.
+   To start a regular task worker: celery -A celery_app.celery_app worker --loglevel=info
+   To start a periodic task scheduler (beat): celery -A celery_app.celery_app beat --loglevel=info
    ```
 
 ### Frontend
@@ -231,6 +234,10 @@ git clone https://gitee.com/tao__tao/fastapi_vue3_admin.git
 
 ![Cache](./mkdocs/docs/resources/images/cache.png)
 
+### Task
+
+![Task](./mkdocs/docs/resources/images/task.jpeg)
+
 ### API
 
 ![API](./mkdocs/docs/resources/images/docs.png)