feat: Implement UGUI

[Bli-AIk]

🔗 Is your feature request related to a specific issue?

For projects built on the Unity engine, leveraging the native Unity UI (UGUI) system is often the most performant and well-integrated solution. The MooaLewaUI framework needs a backend that can target UGUI to be a viable option for Unity developers.

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💡 Feature Description

Create a UGUI rendering backend for MooaLewaUI. This implementation will translate the framework's abstract UI tree into a hierarchy of UGUI GameObjects, Canvases, and Components.

• Expected outcome or effect: The ability to render the framework's XAML-defined UI using the native, high-performance UGUI system in Unity.
• Specific implementation ideas: The following definitions are for reference only and are subject to change. Implementation could include:
  • A set of UGUIButton, UGUITextBlock classes that implement the abstract control interfaces from the core UI framework.
  • These classes will wrap UGUI components (e.g., UnityEngine.UI.Button, TMPro.TextMeshProUGUI).
  • A UGUIRenderer will be responsible for creating and managing the UGUI object hierarchy under a Canvas.
• Usage scenarios or benefits: This provides a high-performance, engine-native UI solution for Unity users. It allows them to benefit from the framework's architecture (XAML, data binding) while still getting the performance and editor integration of UGUI.

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⚖ Alternatives Considered

N/A

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📝 Additional Information

This will be an engine-specific implementation, likely housed in a separate assembly or package (e.g., Lunar.Framework.MooaLewaUI.Unity).