MM-57326: [Shared Channels] Message priority, acknowledgement and persistent notifications need to be synced (#30736)

server/platform/services/sharedchannel/sync_send.go

@@ -469,6 +469,9 @@ func (scs *Service) handlePostError(postId string, task syncTask, rc *model.Remo
 		return
 	}
 
+	// Populate metadata for the retry post
+	post = scs.app.PreparePostForClient(request.EmptyContext(scs.server.Log()), post, false, false, true)
+
 	syncMsg := model.NewSyncMsg(task.channelID)
 	syncMsg.Posts = []*model.Post{post}