✨ feat: enhance post retrieval with authorization token

- Updated `getPostById` function to accept an optional authorization token.
- Modified `PostPage` to retrieve the token from cookies and pass it to the API call.
- Added smooth transition effects for background and text colors in `globals.css`.
- Cleaned up imports and formatting in `blog-home.tsx`.
- Refactored `blog-post.tsx` to use `MDXRemote` for rendering markdown content.
- Introduced `blog-comment.tsx` and `blog-post-header.client.tsx` components for better structure.
- Added a switch component for dark/light mode toggle in the navbar.
- Updated `Post` model to include a description field.

web/src/app/globals.css

@@ -120,3 +120,7 @@
     @apply bg-background text-foreground;
   }
 }
+
+html, body {
+  transition: background-color 0.3s, color 0.3s !important;
+}