Implemented core logic

GifResizer/App.xaml.cs

@@ -1,6 +1,7 @@
 using System.Configuration;
 using System.Data;
 using System.Windows;
+using GifResizer.Service;
 using GifResizer.ViewModels;
 using GifResizer.Views;
 
@@ -15,7 +16,7 @@ public partial class App : Application
     {
         base.OnStartup(e);
         
-        var viewModel = new MainViewModel();
+        var viewModel = new MainViewModel(new ResizeService());
         var mainWindow = new MainWindow(viewModel);
         
         mainWindow.Show();