add username

src/components/PostItem.tsx

@@ -1,4 +1,5 @@
 import { Post } from '../model/posts/posts.ts'
+import { Link } from 'react-router'
 
 interface PostItemProps {
   post: Post
@@ -15,7 +16,12 @@ export default function PostItem({ post }: PostItemProps) {
 
   return (
     <article className="w-full p-4" key={post.postId}>
-      <div className="text-sm text-gray-500 mb-3">{formattedDate}</div>
+      <div className="text-sm text-gray-500 mb-3">
+        <Link to={`/u/${post.authorName}`} className="text-gray-400 hover:underline mr-2">
+          @{post.authorName}
+        </Link>
+        • {formattedDate}
+      </div>
 
       <div className="text-gray-800 mb-4 whitespace-pre-wrap">{post.content}</div>