TF-933 Update new position EmptyTrashNow button in mailbox trash on Web Desktop

lib/features/mailbox_dashboard/presentation/controller/mailbox_dashboard_controller.dart

@@ -680,6 +680,12 @@ class MailboxDashBoardController extends ReloadableController {
     dispatchAction(StartSearchEmailAction());
   }
 
+  bool get isMailboxTrash => selectedMailbox.value?.isTrash == true;
+
+  void emptyTrashAction(BuildContext context) {
+    dispatchAction(EmptyTrashAction(context));
+  }
+
   @override
   void onClose() {
     _emailReceiveManager.closeEmailReceiveManagerStream();