Fixed self snapping for copied layer

src/PixiEditor/ViewModels/SubViewModels/ToolsViewModel.cs

@@ -449,15 +449,22 @@ internal class ToolsViewModel : SubViewModel<ViewModelMain>, IToolsHandler
         if (e.OldDocument is not null)
         {
             e.OldDocument.PropertyChanged -= DocumentOnPropertyChanged;
+            e.OldDocument.LayersChanged -= DocumentOnLayersChanged;
         }
 
         if (e.NewDocument is not null)
         {
             e.NewDocument.PropertyChanged += DocumentOnPropertyChanged;
+            e.NewDocument.LayersChanged += DocumentOnLayersChanged;
             UpdateEnabledState();
         }
     }
 
+    private void DocumentOnLayersChanged(object? sender, LayersChangedEventArgs e)
+    {
+        UpdateEnabledState();
+    }
+
     private void DocumentOnPropertyChanged(object? sender, PropertyChangedEventArgs e)
     {
         if (e.PropertyName == nameof(DocumentViewModel.SelectedStructureMember))