Add comprehensive tests for image processing nodes and refactor node imports

- Introduced new test files for image layer, image plane, normal scale, object normal rotation, shadeless, and temporary attributes.
- Implemented tests to validate the behavior of alpha curves, depth layers, and normal scales in various rendering engines.
- Refactored import paths for node groups to align with the new directory structure.
- Added checks for temporary attribute lifetimes and ensured proper cleanup without warnings.
- Enhanced CLI commands to require the Blender group and validate the presence of generated node assets before packaging.
- Updated packaging scripts to enforce the existence of necessary assets, preventing build failures.

pyproject.toml

@@ -46,7 +46,7 @@ requires = ["hatchling"]
 build-backend = "hatchling.build"
 
 [tool.hatch.build.targets.wheel]
-packages = ["tools"]
+packages = ["src/anyimage", "tools", "nodes"]
 
 [tool.pytest.ini_options]
 # Keep native asserts: bpy 4.5 can crash at shutdown after assertion rewriting.