updated project dependencies and sdk. Comptaible with Flutter 3.35.3

lib/widget/fileViewer.dart

@@ -1,8 +1,8 @@
 import 'dart:io';
 import 'dart:math';
 
-import 'package:better_open_file/better_open_file.dart';
 import 'package:flutter/material.dart';
+import 'package:open_filex/open_filex.dart';
 import 'package:photo_view/photo_view.dart';
 import 'package:provider/provider.dart';
 import 'package:share_plus/share_plus.dart';
@@ -93,7 +93,7 @@ class _FileViewerState extends State<FileViewer> {
         );
 
       default:
-        OpenFile.open(widget.path).then((result) {
+        OpenFilex.open(widget.path).then((result) {
           Navigator.of(context).pop();
           if(result.type != ResultType.done) {
             showDialog(context: context, builder: (context) => AlertDialog(