feat: Implement AI Agent with enhanced tool processing capabilities (#89)

* feat: Implement AI Agent with tool processing capabilities

- Added tools for listing and running processors in the agent.
- Created data models for agent chat requests and tool calls.
- Developed API integration for agent chat and streaming responses.
- Built the AI Agent widget with a user interface for interaction.
- Styled the agent components for better user experience.

* feat: 增强 AI 助手工具功能，添加文件操作和搜索功能，更新界面显示

* feat: 更新 AI 助手组件

* feat: 更新 AiAgentWidget 组件样式，调整背景和边距以提升界面一致性

api/routers.py

@@ -11,6 +11,7 @@ from domain.processors import api as processors
 from domain.share import api as share
 from domain.tasks import api as tasks
 from domain.ai import api as ai
+from domain.agent import api as agent
 from domain.virtual_fs import api as virtual_fs
 from domain.virtual_fs.mapping import s3_api, webdav_api
 from domain.virtual_fs.search import search_api
@@ -30,6 +31,7 @@ def include_routers(app: FastAPI):
     app.include_router(backup.router)
     app.include_router(ai.router_vector_db)
     app.include_router(ai.router_ai)
+    app.include_router(agent.router)
     app.include_router(plugins.router)
     app.include_router(webdav_api.router)
     app.include_router(s3_api.router)