Disabled out of date fix for files, and disabled file download in staging

lib/view/pages/files/fileElement.dart

@@ -6,11 +6,13 @@ import 'package:flowder/flowder.dart';
 import 'package:flutter/foundation.dart';
 import 'package:flutter/material.dart';
 import 'package:jiffy/jiffy.dart';
+import 'package:marianum_mobile/widget/infoDialog.dart';
 import 'package:nextcloud/nextcloud.dart';
 import 'package:path_provider/path_provider.dart';
 
 import '../../../api/marianumcloud/webdav/queries/listFiles/cacheableFile.dart';
 import '../../../api/marianumcloud/webdav/webdavApi.dart';
+import '../../../model/endpointData.dart';
 import '../../../widget/centeredLeading.dart';
 import '../../../widget/confirmDialog.dart';
 import '../../../widget/fileViewer.dart';
@@ -103,6 +105,10 @@ class _FileElementState extends State<FileElement> {
             },
           ));
         } else {
+          if(EndpointData().getEndpointMode() == EndpointMode.stage) {
+            InfoDialog.show(context, "Virtuelle Dateien im Staging Prozess können nicht heruntergeladen werden!");
+            return;
+          }
           if(widget.file.currentlyDownloading) {
             showDialog(
               context: context,