Add tests for clipboard image functionality and mesh plane asset creation

- Implemented a comprehensive test suite for the clipboard image module, covering various functionalities including operator registration, context handling, and image processing.
- Created a new mesh plane asset with customizable parameters and integrated it into the geometry node system.
- Developed a validation script to ensure the correct behavior of the mesh plane asset, including input handling and output verification.

docs/guide-surface.md

@@ -16,7 +16,7 @@ Surface 从单张图片构建带透视关系的纹理网格。它适合建筑、
 
 默认的 **MoGe-2 ViT-S Normal** 适合多数图片。MoGe-2 使用 **Resolution Level**，DA3 使用 **Resolution Scale**。提高分辨率会增加耗时和内存占用，建议先用默认值判断整体结构。
 
-如果某个模型名称后显示 **(Missing)**，请先在 3D View 的 **AnyImage > Models** 面板下载它。
+如果某个模型名称后显示 **(Missing)**，请在 AnyImage 扩展偏好设置中下载它。右键菜单底部的 **AI Environment Settings…** 可以直接打开对应设置。
 
 ## 转换选项