Refactor depth node groups and simplify options

- Removed `Smooth Weight` input from `O Image Depth Plane`, `O Image Depth Cutout`, and `O Image Depth Panorama` to streamline the interface and maintain consistent boundary smoothing behavior.
- Adjusted the `Reference Depth` input to appear last in the options panel for better organization, reflecting its role as a calibration value.
- Consolidated the `expand_smooth()` function to only accept necessary parameters, eliminating unused branches related to `Smooth Weight` and `pin_sharp`.
- Updated related tests and node assets to ensure functionality remains intact and consistent with the new structure.
- Introduced new specifications to document the changes and ensure compliance with the updated requirements.

tests/support/depth_surface.py

@@ -91,6 +91,30 @@ def assert_closed(faces):
     assert edges and set(edges.values()) == {2}, Counter(edges.values())
 
 
+def assert_single_vertex_fans(faces):
+    """Every vertex must close one face fan so touching sheets stay identifiable."""
+    incident = {}
+    for index, face in enumerate(faces):
+        for start, end in zip(face, (*face[1:], face[0])):
+            edge = tuple(sorted((start, end)))
+            incident.setdefault(start, {}).setdefault(edge, []).append(index)
+            incident.setdefault(end, {}).setdefault(edge, []).append(index)
+    for vertex, edges in incident.items():
+        shared = {}
+        for faces_at_edge in edges.values():
+            assert len(faces_at_edge) == 2, (vertex, faces_at_edge)
+            first, second = faces_at_edge
+            shared.setdefault(first, set()).add(second)
+            shared.setdefault(second, set()).add(first)
+        assert all(len(neighbors) == 2 for neighbors in shared.values()), vertex
+        reached, pending = {next(iter(shared))}, [next(iter(shared))]
+        while pending:
+            for neighbor in shared[pending.pop()] - reached:
+                reached.add(neighbor)
+                pending.append(neighbor)
+        assert len(reached) == len(shared), vertex
+
+
 def component_count(faces):
     adjacency = {}
     for face in faces:

tests/support/image_objects.py

@@ -3,7 +3,6 @@ import numpy as np
 
 
 from anyimage.common import image as image_data
-from anyimage.common import object as object_data
 from anyimage.common.selection import SelectionMask
 from anyimage.operators.cutout_tool import geometry as cutout_geometry
 from anyimage.operators.cutout_tool import object as cutout_object
@@ -107,18 +106,3 @@ def _evaluated_positions(obj):
         evaluated.to_mesh_clear()
 
 
-def _add_cutout_modifier(obj, shape):
-    group = cutout_object.load_cutout_node_group(shape)
-    modifier = obj.modifiers.new(group.name, "NODES")
-    modifier.node_group = group
-    if shape in {"FLAT", "DEPTH_SOLID"}:
-        object_data.set_modifier_input(modifier, object_data.modifier_input_identifier(group, "Mode"), 1)
-    if shape == "DEPTH_SOLID":
-        object_data.set_modifier_input(
-            modifier,
-            object_data.modifier_input_identifier(group, "Smooth Weight"),
-            0.0,
-        )
-    return modifier
-
-