Add tests and implement boundary smoothing and cutout functionality

- Introduced tests for boundary smoothing in `test_boundary_smoothing.py`, verifying that smoothing reduces stair-step artifacts while preserving boundary integrity.
- Added tests for cutout boundary behavior in `test_cutout_boundary.py`, ensuring proper handling of boundary triangles and normal blending.
- Created `test_temporary_attributes.py` to check the cleanup of temporary attributes across depth modifier branches, ensuring no warnings are raised.
- Implemented point culling functionality in `test_validity.py`, confirming that invalid points are removed without affecting adjacent geometry.
- Developed boundary smoothing logic in `boundary_smoothing.py`, allowing for depth smoothing while maintaining edge integrity.
- Added cutout boundary management in `cutout_boundary.py`, including functions for removing boundary triangles and tapering thickness profiles.
- Implemented validity checks in `validity.py` to ensure proper deletion of invalid vertices and associated wire edges.

tools/nodes/common/material.py

@@ -3,20 +3,23 @@
 
 def inherit_material_slots(group, geometry, source):
     nodes, links = group.nodes, group.links
-    capture = nodes.new("GeometryNodeCaptureAttribute")
-    capture.domain = "POINT"
-    capture.capture_items.clear()
-    capture.capture_items.new("BOOLEAN", "Source")
-    capture.inputs["Source"].default_value = True
-    links.new(source, capture.inputs["Geometry"])
+    size = nodes.new("GeometryNodeAttributeDomainSize")
+    size.component = "MESH"
+    links.new(source, size.inputs["Geometry"])
+    index = nodes.new("GeometryNodeInputIndex")
+    source_vertices = nodes.new("FunctionNodeCompare")
+    source_vertices.data_type, source_vertices.operation = "INT", "LESS_THAN"
+    links.new(index.outputs["Index"], source_vertices.inputs[2])
+    links.new(size.outputs["Point Count"], source_vertices.inputs[3])
     join = nodes.new("GeometryNodeJoinGeometry")
+    # Multi-input links are prepended: source occupies the first point range.
     links.new(geometry, join.inputs["Geometry"])
-    links.new(capture.outputs["Geometry"], join.inputs["Geometry"])
+    links.new(source, join.inputs["Geometry"])
     material = nodes.new("GeometryNodeSetMaterialIndex")
     material.inputs["Material Index"].default_value = 0
     links.new(join.outputs["Geometry"], material.inputs["Geometry"])
     delete = nodes.new("GeometryNodeDeleteGeometry")
     delete.domain = "POINT"
     links.new(material.outputs["Geometry"], delete.inputs["Geometry"])
-    links.new(capture.outputs["Source"], delete.inputs["Selection"])
+    links.new(source_vertices.outputs["Result"], delete.inputs["Selection"])
     return delete.outputs["Geometry"]