Refactor application structure and add unit tests

Added:
- New `ProgressService` class for managing progress indicators.
- New `AssetDatabase`, `AssetOpenHandlerAttribute`, and `AsyncAssetOpenHandlerAttribute` classes for asset handling.
- `Ghost.UnitTest` project for unit testing with associated files and configurations.

Changed:
- `ActivationHandler` class to ensure correct handling of `LaunchActivatedEventArgs`.
- `App.xaml.cs` to register `INotificationService` and `IProgressService`, replacing `StackedNotificationService`.
- `OnLaunched` method in `App.xaml.cs` to correctly call `ActivationHandler.Handle(args)` and start the host.
- `INavigationAware` interface from internal to public for broader access.
- `EditorState.cs` to activate `EditorApplication` with the current service provider.
- Property names in `AssetItem` and `ExplorerItem` structs to `Name` and `FullName`.
- `NotificationService` class to implement `INotificationService` and refactor notification handling.
- `AssetPathToGlyphConverter` to handle file extensions consistently.
- Bindings in `ProjectPage.xaml` and `ProjectPage.xaml.cs` to use `FullName` instead of `Path`.
- `EngineEditorWindow` and `LandingWindow` classes to utilize new notification and progress services.
- `Logger` class to include a new method for logging errors with exceptions.

Updated:
- Manifest files and project files to reflect new structure and dependencies.
- Solution file `GhostEngine.sln` to include the new unit test project.
- Added several new test classes and methods in `UnitTests.cs`.

Ghost.App/Utilities/ComponentTypeCache.cs

@@ -0,0 +1,30 @@
+using Ghost.Entities;
+using System;
+using System.Linq;
+
+namespace Ghost.App.Utilities;
+
+public static class ComponentTypeCache
+{
+    private static readonly Type?[][] _componentTypes;
+
+    static ComponentTypeCache()
+    {
+        _componentTypes = new Type[World.WorldCount][];
+        for (var i = 0; i < World.WorldCount; i++)
+        {
+            var world = World.GetWorld(i);
+            var typeHandles = world.ComponentStorage.ComponentPools.Keys;
+            _componentTypes[i] = typeHandles.Select(handle => Type.GetTypeFromHandle(RuntimeTypeHandle.FromIntPtr(handle))).ToArray();
+        }
+    }
+
+    public static Type?[] GetComponentTypes(int worldIndex)
+    {
+        if (worldIndex < 0 || worldIndex >= _componentTypes.Length)
+        {
+            throw new ArgumentOutOfRangeException(nameof(worldIndex), "Invalid world index.");
+        }
+        return _componentTypes[worldIndex];
+    }
+}

Ghost.App/Utilities/Converters/AssetPathToGlyphConverter.cs

@@ -0,0 +1,41 @@
+using Microsoft.UI.Xaml.Data;
+using System;
+using System.IO;
+
+namespace Ghost.Editor.Utilities.Converters;
+
+public partial class AssetPathToGlyphConverter : IValueConverter
+{
+    public object? Convert(object value, Type targetType, object parameter, string language)
+    {
+        if (value is not string path)
+        {
+            return null;
+        }
+
+        if (Directory.Exists(path))
+        {
+            return "\uE8B7";
+        }
+
+        var extension = Path.GetExtension(path).ToLowerInvariant();
+
+        // TODO: Use resource dictionary for icons.
+        return extension switch
+        {
+            ".ghostscene" => "\uF159",
+            ".fbx" or ".obj" => "\uF158",
+            ".png" or ".jpg" or ".jpeg" or ".gif" or ".bmp" => "\uE91B",
+            ".mp3" or ".wav" or ".ogg" => "\uE767",
+            ".mp4" or ".avi" or ".mkv" => "\uE714",
+            ".txt" or ".md" => "\uF000",
+            ".cs" or ".hlsl" => "\uE943",
+            _ => "\uE8A5",
+        };
+    }
+
+    public object ConvertBack(object value, Type targetType, object parameter, string language)
+    {
+        throw new NotImplementedException();
+    }
+}

Ghost.App/Utilities/Converters/GetDirectoryNameConverter .cs

@@ -0,0 +1,17 @@
+using Microsoft.UI.Xaml.Data;
+using System;
+
+namespace Ghost.Editor.Utilities.Converters;
+
+public partial class GetDirectoryNameConverter : IValueConverter
+{
+    public object? Convert(object value, Type targetType, object parameter, string language)
+    {
+        return value is string path ? System.IO.Path.GetDirectoryName(path) : null;
+    }
+
+    public object? ConvertBack(object value, Type targetType, object parameter, string language)
+    {
+        throw new NotImplementedException();
+    }
+}

Ghost.App/Utilities/HostHelpers.Page.cs

@@ -0,0 +1,45 @@
+using Ghost.App.View.Pages.EngineEditor;
+using Ghost.App.View.Pages.Landing;
+using Ghost.App.View.Windows;
+using Ghost.Data.Services;
+using Ghost.Editor.ViewModels.Pages.EngineEditor;
+using Ghost.Editor.ViewModels.Pages.Landing;
+using Ghost.Editor.ViewModels.Windows;
+using Ghost.Engine;
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Hosting;
+
+namespace Ghost.App.Utilities;
+
+internal static partial class HostHelper
+{
+    public static void AddLandingScope(HostBuilderContext context, IServiceCollection services)
+    {
+        services.AddTransient<LandingWindow>();
+
+        services.AddTransient<CreateProjectPage>();
+        services.AddTransient<CreateProjectViewModel>();
+
+        services.AddTransient<OpenProjectPage>();
+        services.AddTransient<OpenProjectViewModel>();
+
+        services.AddTransient<ProjectService>();
+    }
+
+    public static void AddEngineScope(HostBuilderContext context, IServiceCollection services)
+    {
+        services.AddSingleton<EngineCore>();
+
+        services.AddTransient<EngineEditorWindow>();
+        services.AddTransient<EngineEditorViewModel>();
+
+        services.AddTransient<HierarchyPage>();
+        services.AddTransient<HierarchyViewModel>();
+
+        services.AddTransient<ProjectPage>();
+        services.AddTransient<ProjectViewModel>();
+
+        services.AddTransient<ConsolePage>();
+        services.AddTransient<ConsoleViewModel>();
+    }
+}

Ghost.App/Utilities/SystemUtilities.cs

@@ -0,0 +1,42 @@
+using System;
+using System.Collections.Generic;
+using System.Threading.Tasks;
+using Windows.Storage;
+using Windows.Storage.Pickers;
+using WinRT.Interop;
+
+namespace Ghost.App.Utilities;
+
+public static class SystemUtilities
+{
+    public static async Task<StorageFolder?> OpenFolderPickerAsync(PickerLocationId startLocation = PickerLocationId.DocumentsLibrary, string settingsIdentifier = "")
+    {
+        var openPicker = new FolderPicker();
+        var hWnd = WindowNative.GetWindowHandle(GhostApplication.Window);
+        InitializeWithWindow.Initialize(openPicker, hWnd);
+
+        openPicker.SuggestedStartLocation = startLocation;
+        openPicker.FileTypeFilter.Add("*");
+        openPicker.SettingsIdentifier = settingsIdentifier;
+
+        var folder = await openPicker.PickSingleFolderAsync();
+        return folder;
+    }
+
+    public static async Task<StorageFile?> OpenFilePickerAsync(PickerLocationId startLocation = PickerLocationId.DocumentsLibrary, string settingsIdentifier = "", params IEnumerable<string> filter)
+    {
+        var openPicker = new FileOpenPicker();
+        var hWnd = WindowNative.GetWindowHandle(GhostApplication.Window);
+        InitializeWithWindow.Initialize(openPicker, hWnd);
+
+        openPicker.SuggestedStartLocation = startLocation;
+        openPicker.SettingsIdentifier = settingsIdentifier;
+        foreach (var fileType in filter)
+        {
+            openPicker.FileTypeFilter.Add(fileType);
+        }
+
+        var file = await openPicker.PickSingleFileAsync();
+        return file;
+    }
+}