Refactor project management and enhance architecture

Added a new static class `AssetsPath` for asset management.
Added a new icon file (`icon-256.ico`) for UI representation.
Added new package references to enhance functionality.
Added internals visibility attributes for better testing.
Added a new `EngineEditorViewModel` class for MVVM support.
Added a new `GameObject` class for component management.
Added a new `BitSet` class for efficient bit manipulation.
Added various utility classes to support the new entity system.

Changed the `ID` property in `ProjectInfo` to internal.
Changed the `AddProjectAsync` method to return the created `ProjectInfo`.
Changed the connection string retrieval method to use the new `Command` constant.
Changed the `DataPath` class to use `readonly` fields for folder paths.
Changed the `ActivationHandler` class to use new `DataPath` constants.
Changed the `OpenProjectPage` layout and interaction for better UI.

Updated the target framework to a newer version for compatibility.
Updated the `ProjectService` to use new constants from `DataPath`.
Updated the `World` class to improve entity management.

Refactored the `ProjectRepository` class to encapsulate SQL commands.
Refactored the `Transform` class to use properties for better encapsulation.

Ghost.Entities/Signature.cs

@@ -0,0 +1,38 @@
+using Misaki.HighPerformance.Unsafe.Collections;
+using Misaki.HighPerformance.Unsafe.Helpers;
+
+namespace Ghost.Entities;
+
+internal struct Signature : IDisposable
+{
+    internal UnsafeArray<ComponentData> _componentDatas;
+    private int _hashCode;
+
+    public Signature(params Span<ComponentData> components)
+    {
+        _componentDatas = new UnsafeArray<ComponentData>(components.Length, Allocator.Persistent);
+        _componentDatas.CopyFrom(components);
+
+        _hashCode = -1;
+        _hashCode = GetHashCode();
+    }
+
+    public override int GetHashCode()
+    {
+        if (_hashCode != -1)
+        {
+            return _hashCode;
+        }
+
+        unchecked
+        {
+            _hashCode = Component.GetHashCode(_componentDatas.AsSpan());
+            return _hashCode;
+        }
+    }
+
+    public void Dispose()
+    {
+        _componentDatas.Dispose();
+    }
+}