Fix manual handler registrations

Framework/Avalonia/Contents/ContentHandler.cs

@@ -1,6 +1,5 @@
 using Avalonia;
 using Mediator;
-using System.Diagnostics;
 using Toolkit.Framework.Foundation;
 
 namespace Toolkit.Framework.Avalonia;

Framework/Avalonia/Extensions/IServiceCollectionExtensions.cs

@@ -6,10 +6,11 @@ namespace Toolkit.Framework.Avalonia;
 
 public static class IServiceCollectionExtensions
 {
-    public static IServiceCollection AddNavigation(this IServiceCollection serviceCollection)
+    public static IServiceCollection AddAvalonia(this IServiceCollection serviceCollection)
     {
         serviceCollection.TryAddSingleton<INavigationRouteDescriptorCollection, NavigationRouteDescriptorCollection>();
 
+        serviceCollection.AddHandler<ContentHandler>();
         serviceCollection.AddHandler<NavigationRouteHandler>();
         serviceCollection.AddHandler<NavigateHandler>();
         serviceCollection.AddHandler<FrameNavigationHandler>();

Framework/Avalonia/Navigation/ContentControlNavigationHandler.cs

@@ -5,7 +5,7 @@ namespace Toolkit.Framework.Avalonia;
 
 public class ContentControlNavigationHandler : IRequestHandler<ContentControlNavigation, bool>
 {
-    public async ValueTask<bool> Handle(ContentControlNavigation request, CancellationToken cancellationToken)
+    public ValueTask<bool> Handle(ContentControlNavigation request, CancellationToken cancellationToken)
     {
         if (request.Template is TemplatedControl control)
         {
@@ -13,6 +13,6 @@ public class ContentControlNavigationHandler : IRequestHandler<ContentControlNav
             request.Route.Content = control;
         }
 
-        return await Task.FromResult(true);
+        return new ValueTask<bool>(true);
     }
 }

Framework/Foundation/Extensions/IServiceCollectionExtensions.cs

@@ -37,6 +37,7 @@ public static class IServiceCollectionExtensions
             .AddSingleton<IMediator, Mediator>()
             .AddHandler<InitializeHandler>()
             .AddSingleton<IServiceFactory>(provider => new ServiceFactory(provider.GetService, (instanceType, parameters) => ActivatorUtilities.CreateInstance(provider, instanceType, parameters!)))
+            .AddHandler<ServiceFactoryHandler>()
             .AddSingleton<IInitialization, Initialization>(provider => new Initialization(() =>
             {
                 return serviceCollection.Where(x => x.ServiceType.GetInterfaces()