feat: Implement weight cutout boundary smoothing for image depth cutout

- Added a new proposal for boundary smoothing in the weight cutout process, differentiating between Split edges and Outline smoothing requirements.
- Introduced a new capability `cutout-boundary-smoothing` to control smoothing strength and default values.
- Updated specifications to define the behavior of boundary-specific smoothing strength and default settings.
- Created tasks to verify the implementation of boundary behavior and asset updates.
- Developed comprehensive tests for depth symmetry and normal scaling to ensure expected behavior and performance.
- Introduced new attributes for normal mapping to facilitate persistent face attributes sharing between depth symmetry and image materials.
- Built a new node group for O Image Depth Symmetry, integrating the new smoothing capabilities and ensuring compatibility with existing workflows.

tests/anyimage/operators/test_cutout_objects.py

@@ -175,22 +175,10 @@ def test_balloon_build_starts_from_the_unified_single_sheet():
     profile_attribute.data.foreach_get("value", profile)
     assert profile.min() == 0.0 and profile.max() > 0.0
     material_tree = result.data.materials[0].node_tree
-    normal_scale_attribute = next(
-        node
-        for node in material_tree.nodes
-        if node.bl_idname == "ShaderNodeAttribute"
-    )
-    assert normal_scale_attribute.attribute_type == "GEOMETRY"
-    assert normal_scale_attribute.attribute_name == cutout_shape.NORMAL_SCALE_ATTRIBUTE_NAME
+    assert not any(node.bl_idname == "ShaderNodeAttribute" for node in material_tree.nodes)
     image_layer = _group_node(material_data.material_node_group(), material_tree)
-    normal_scale_link = next(
-        link
-        for link in material_tree.links
-        if link.to_node == image_layer
-        and link.to_socket == image_layer.inputs["Normal Scale"]
-    )
-    assert normal_scale_link.from_node == normal_scale_attribute
-    assert normal_scale_link.from_socket == normal_scale_attribute.outputs["Fac"]
+    assert not image_layer.inputs["Normal Scale"].is_linked
+    assert image_layer.inputs["Normal Scale"].default_value == 1.0
     assert result.modifiers[0].node_group.name == cutout_shape.CUTOUT_NODE_GROUP_NAMES["SOLID"]
     inward = result.matrix_world.to_3x3() @ Vector((0.0, 0.0, -1.0))
     assert np.allclose(tuple(inward), (0.0, 0.0, -1.0), atol=1e-6)
@@ -219,7 +207,7 @@ def test_teddy_preference_writes_the_shared_balloon_attribute():
     profile = np.empty(len(result.data.vertices), dtype=np.float32)
     attribute.data.foreach_get("value", profile)
     assert profile.min() == 0.0 and profile.max() > 0.0
-    assert any(
+    assert not any(
         node.bl_idname == "ShaderNodeAttribute"
         for node in result.data.materials[0].node_tree.nodes
     )
@@ -585,10 +573,11 @@ def test_cutout_cleanup_uses_absolute_area_with_many_small_islands():
     assert len(_evaluated_positions(obj)) == 9
 
 
-def test_depth_balloon_uses_metric_plane_inputs():
+@pytest.mark.parametrize("gesture", ("LASSO", "POLYLINE"))
+def test_depth_symmetry_uses_metric_plane_inputs(gesture):
     bpy.ops.wm.read_factory_settings(use_empty=True)
-    image = bpy.data.images.new("Depth Balloon", width=100, height=100, alpha=True)
-    source = bpy.data.objects.new("Depth Balloon", None)
+    image = bpy.data.images.new("Depth Symmetry", width=100, height=100, alpha=True)
+    source = bpy.data.objects.new("Depth Symmetry", None)
     source.empty_display_type = "IMAGE"
     source.data = image
     source.empty_display_size = 2.0
@@ -619,12 +608,13 @@ def test_depth_balloon_uses_metric_plane_inputs():
     selection_values[:, :2] = 0.0
     result = _create_cutout_shape(
         source,
-        "DEPTH_BALLOON",
+        "DEPTH_SYMMETRY",
         0.1,
         depth_image=depth_image,
         depth_metadata=depth_metadata,
         bounds=crop_bounds,
         selection_values=selection_values,
+        gesture=gesture,
     )
 
     assert all(abs(vertex.co.z) < 1e-8 for vertex in result.data.vertices)
@@ -634,6 +624,9 @@ def test_depth_balloon_uses_metric_plane_inputs():
         result.name,
     }
     modifier = result.modifiers[0]
+    mode_id = object_data.modifier_input_identifier(modifier.node_group, "Mode")
+    assert modifier_value(modifier, mode_id) == 1
+    object_data.set_modifier_input(modifier, mode_id, 0)
     depth_image_id = object_data.modifier_input_identifier(
         modifier.node_group,
         "Depth Image",