Added option to open FileViewer always with system dialog, enabled by default on iOS

lib/storage/base/settingsProvider.dart

@@ -1,6 +1,8 @@
 import 'dart:convert';
 import 'dart:developer';
+import 'dart:io';
 import 'package:flutter/material.dart';
+import 'package:marianum_mobile/storage/fileView/fileViewSettings.dart';
 import 'package:shared_preferences/shared_preferences.dart';
 
 import '../../view/pages/files/files.dart';
@@ -100,6 +102,9 @@ class SettingsProvider extends ChangeNotifier {
         dismissedDisclaimer: false,
         showPastEvents: false,
       ),
+      fileViewSettings: FileViewSettings(
+        alwaysOpenExternally: Platform.isIOS,
+      ),
     );
   }
 }