Update calendar and preview to show past scheduled posts

Refactor `RecentPublications` to filter and sort attempted posts using `scheduledAt` timestamp. Update `PreviewModal` and `CalendarView` to include a `readOnly` prop for the preview modal.

Replit-Commit-Author: Agent
Replit-Commit-Session-Id: ae4037a0-2a6f-4530-9bac-79b543286bda
Replit-Commit-Checkpoint-Type: intermediate_checkpoint
Replit-Commit-Screenshot-Url: https://storage.googleapis.com/screenshot-production-us-central1/397bca8c-984f-43ff-841a-10897aeb8140/ae4037a0-2a6f-4530-9bac-79b543286bda/oa3970R

client/src/components/recent-publications.tsx

@@ -23,10 +23,11 @@ export default function RecentPublications() {
     queryKey: ['/api/scheduled-posts'],
   });
 
-  // Filter and sort published posts
+  // Filter and sort attempted posts (scheduled in the past)
+  const now = new Date();
   const recentPublished = scheduledPosts
-    .filter(sp => sp.publishedAt)
-    .sort((a, b) => new Date(b.publishedAt!).getTime() - new Date(a.publishedAt!).getTime())
+    .filter(sp => sp.scheduledAt && new Date(sp.scheduledAt) <= now)
+    .sort((a, b) => new Date(b.scheduledAt!).getTime() - new Date(a.scheduledAt!).getTime())
     .slice(0, 10);
 
   const handlePreviewPost = async (scheduledPost: ScheduledPostWithRelations) => {
@@ -141,7 +142,7 @@ export default function RecentPublications() {
                     </span>
                     <span>•</span>
                     <span>
-                      {format(new Date(scheduledPost.publishedAt!), "d MMM yyyy 'à' HH:mm", { locale: fr })}
+                      {format(new Date(scheduledPost.scheduledAt!), "d MMM yyyy 'à' HH:mm", { locale: fr })}
                     </span>
                     {scheduledPost.error && (
                       <>
@@ -165,6 +166,7 @@ export default function RecentPublications() {
         mediaList={previewData.allMedia}
         onPublish={() => {}}
         isPublishing={false}
+        readOnly={true}
       />
     </Card>
   );