Add new node asset scripts for geometry and shader operations

- Implemented `build_mesh_plane.py` to create a geometry node group for mesh planes with customizable parameters.
- Created `build_shadeless.py` for a shader node group that displays color without scene lighting while preserving shadows and reflections.
- Added `validate.py` to validate the integrity of the newly created node groups and their inputs.
- Introduced `validate_cutout.py` to ensure the functionality of cutout node groups and their dependencies.
- Developed `validate_mesh_plane.py` to test the mesh plane creation and its modifier settings.

tests/test_cutout.py

@@ -8,8 +8,8 @@ import bpy
 SOURCE_ROOT = Path(__file__).parents[1] / "src"
 sys.path.insert(0, str(SOURCE_ROOT))
 
-from anyimage.operators import cutout, mesh
-from anyimage.operators.image_edit.mask import ImageMaskGesture
+from anyimage.operators.common.image_gesture import ImageMaskGesture
+from anyimage.operators.cutout_tool import selection_tool as cutout
 
 
 class Pie:
@@ -54,10 +54,10 @@ def test_cutout_pie_uses_four_semantic_shapes_in_cardinal_order():
     cutout._open_shape_pie(context, object(), source, ((0, 0), (10, 0), (0, 10)))
 
     assert [call[2].shape for call in window_manager.pie.calls] == [
-        mesh.CUTOUT,
-        mesh.BALLOON,
-        mesh.DEPTH_BALLOON,
-        mesh.DEPTH_SURFACE,
+        "CUTOUT",
+        "BALLOON",
+        "DEPTH_BALLOON",
+        "DEPTH_SURFACE",
     ]
     assert [call[1]["text"] for call in window_manager.pie.calls] == [
         "Surface",