Next.js App Router Scaffolding

Generate the complete file-based scaffolding for a new Next.js 14+ application using the App Router. The application is a [app description, e.g., 'a simple to-do list app']. Include the following files with basic boilerplate code: `layout.tsx`, `page.tsx`, a Server Component for data fetching `components/TodoList.tsx`, and a Client Component for interactivity `components/TodoItem.tsx`. Use TypeScript and Tailwind CSS.