feat: add blog posts listing page

app/posts/page.tsx

@@ -0,0 +1,24 @@
+import { getPosts } from '@/lib/posts'
+import { PostCard } from '@/components/blog/PostCard'
+
+export const metadata = { title: 'Posts' }
+
+export default async function PostsPage() {
+  const posts = await getPosts()
+
+  return (
+    <main className="max-w-4xl mx-auto px-6 py-16">
+      <h1 className="font-sans text-4xl font-extrabold tracking-tight lg:text-5xl mt-0 mb-12 text-ink">
+        Posts
+      </h1>
+      <div className="space-y-12">
+        {posts.map((post) => (
+          <PostCard key={post.slug} {...post} />
+        ))}
+        {posts.length === 0 && (
+          <p className="text-ink-soft">No posts yet.</p>
+        )}
+      </div>
+    </main>
+  )
+}