Enhance image editing tests and functionality

- Added parameterized tests for image edit replacement to ensure alpha mode preservation.
- Refactored existing tests to utilize new image editing methods and improve clarity.
- Introduced new tests for image target functionality, ensuring proper handling of shared textures and context.
- Updated various tests to validate alpha mode handling across different scenarios.
- Improved undo/redo functionality in image operators to maintain state consistency.
- Added support for texture node actions, enhancing integration with Blender's node system.
- Ensured that image properties are preserved during operations and that invalid contexts are handled gracefully.

openspec/changes/add-texture-node-image-actions/proposal.md

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+## Why
+
+材质的 Image Texture 节点目前无法直接使用 AnyImage 去背景和放大。用户需要在节点右键菜单中完成处理，并像 Empty Image 一样在当前位置使用结果。
+
+## What Changes
+
+- 在材质 Shader Editor 的有效 Image Texture 节点右键菜单增加 AnyImage 菜单，提供 Remove Background 和 Upscale。
+- 复用现有 AI 环境准备、模型配置、输入限制、任务进度和图片处理流程。
+- 处理成功后原位更新目标节点图片，保留节点、连线及设置；单独使用的图片保留 Image 身份，共享图片仅替换当前节点的绑定。
+- 为异步目标校验、失败恢复、撤销重做和菜单注册增加覆盖。
+
+## Capabilities
+
+### New Capabilities
+
+- `texture-node-image-actions`: 材质 Image Texture 节点的 AI 图片操作入口及原位提交语义。
+
+### Modified Capabilities
+
+无。
+
+## Impact
+
+涉及 `src/anyimage/menu.py`、扩展注册入口、Remove Background / Upscale Operator、`common` 图片输入与提交逻辑及对应测试。服务端沿用现有 Job 协议，依赖和节点资产保持现状。