refactor: integrate TodoListMiddleware and update related components

- Removed the write_todos tool as it is now included by default through TodoListMiddleware in the deep agent.
- Updated the system prompt and documentation to reflect the integration of TodoListMiddleware, clarifying its capabilities for managing planning and todo lists.
- Enhanced the chat handling logic to extract todos directly from the deep agent's command output, ensuring seamless user experience.
- Refactored UI components to align with the new data structure and improve rendering of todo items, including updates to the Plan and TodoItem components.
- Cleaned up code for better maintainability and readability, following recent refactoring efforts.

surfsense_web/components/tool-ui/index.ts

@@ -77,10 +77,4 @@ export {
 	type PlanTodo,
 	type TodoStatus,
 } from "./plan";
-export {
-	WriteTodosToolUI,
-	WriteTodosArgsSchema,
-	WriteTodosResultSchema,
-	type WriteTodosArgs,
-	type WriteTodosResult,
-} from "./write-todos";
+export { WriteTodosToolUI, WriteTodosSchema, type WriteTodosData } from "./write-todos";