fix: use article title as post body instead of bare URL for RSS posts

go-backend/internal/services/official_accounts_service.go

@@ -473,8 +473,8 @@ func (s *OfficialAccountsService) PostNextArticle(ctx context.Context, configID
 	var body string
 	switch cfg.AccountType {
 	case "rss":
-		// Post the link directly
-		body = art.Link
+		// Post the title — the link preview card handles the URL display
+		body = art.Title
 	case "news":
 		// Generate AI commentary
 		rssItem := &RSSItem{
@@ -492,7 +492,7 @@ func (s *OfficialAccountsService) PostNextArticle(ctx context.Context, configID
 		}
 		body = generated
 	default:
-		body = art.Link
+		body = art.Title
 	}
 
 	// Create the post