Add PDF modal and selectedPost setter

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

src/components/PDFModal.tsx

@@ -0,0 +1,27 @@
+import React from 'react'
+import useAppStore from '../store/useAppStore'
+import PDFPreview from './PDFPreview'
+
+const PDFModal: React.FC = () => {
+  const selectedPostId = useAppStore((s) => s.selectedPostId)
+  const setSelectedPost = useAppStore((s) => s.setSelectedPost)
+  const post = useAppStore((s) => s.posts.find((p) => p.id === selectedPostId))
+
+  if (!selectedPostId || !post?.attachedPDF) return null
+
+  return (
+    <div className="modal-backdrop" onClick={() => setSelectedPost(null)}>
+      <div className="modal" onClick={(e) => e.stopPropagation()}>
+        <div style={{display:'flex',justifyContent:'space-between',alignItems:'center'}}>
+          <h3>{post.attachedPDF.name}</h3>
+          <button onClick={() => setSelectedPost(null)}>Close</button>
+        </div>
+        <div style={{marginTop:8}}>
+          <PDFPreview url={post.attachedPDF.url} name={post.attachedPDF.name} />
+        </div>
+      </div>
+    </div>
+  )
+}
+
+export default PDFModal

src/components/PostCard.tsx

@@ -8,6 +8,7 @@ import PDFPreview from './PDFPreview'
 const PostCard: React.FC<{ post: Post }> = ({ post }) => {
   const author = useAppStore((s) => s.users.find((u) => u.id === post.authorId))
   const endorsePost = useAppStore((s) => s.endorsePost)
+  const setSelectedPost = useAppStore((s) => s.setSelectedPost)
 
   if (!author) return null
 
@@ -27,7 +28,11 @@ const PostCard: React.FC<{ post: Post }> = ({ post }) => {
       <p style={{marginTop:8}}>{post.content}</p>
       {post.attachedPDF && (
         <div style={{marginTop:8}}>
-          <PDFPreview url={post.attachedPDF.url} name={post.attachedPDF.name} />
+          <div className="small">{post.attachedPDF.name}</div>
+          <div style={{marginTop:6,display:'flex',gap:8}}>
+            <button className="button" onClick={() => setSelectedPost(post.id)}>Open PDF</button>
+            <PDFPreview url={post.attachedPDF.url} name={post.attachedPDF.name} />
+          </div>
         </div>
       )}
       <div style={{display:'flex',justifyContent:'space-between',alignItems:'center',marginTop:8}}>