shelldi.cs

 // Option 1
 foreach (var viewModel in assembly.DefinedTypes.Where(e => e.IsSubclassOf(typeof(ViewModel))))
{
    builder.Services.AddTransient(viewModel.GetType());
}

foreach (var view in assembly.DefinedTypes.Where(e => e.IsSubclassOf(typeof(Views.View))))
{
    builder.Services.AddTransient(view.GetType());
}


// Option 2
        builder.Services.AddTransient<LoadingViewModel>();
        builder.Services.AddTransient<LoadingView>();