Project: mobx
Task (easy): 1) An API is prepared, here is the docs of API:
GET /api/blogs
<response_definition>
  interface Response {
    blogs: { title: string; detail:string; }[];
  }
</response_definition>
<response_example>
{
    blogs: [
      { title: 'XXX', detail: 'XXX' },
    ],
  }
</response_example>
2) In stores/blog.ts, add an async action to fetch data from API and update the blog list data in the store.
3) When App.tsx mounted, call the fetch action to start fetching blogs.
4) When API is fetching, show 'Blog is loading' in App.tsx. Use observer in mobx-react-lite to auto update.
5) Notice: When Initial Blog is fetching, Header is always visible but 'Add Blog' button should be disabled.