feat: Implement depth cutout symmetry and associated functionalities

- Introduced a new proposal for depth cutout symmetry, allowing for the reuse of depth replacement and geometry operations.
- Added requirements for maintaining default thickness values for cutout nodes and ensuring proper initialization during object creation.
- Enhanced symmetry node to handle existing geometry, including alignment, mirroring, and boundary filling.
- Implemented fill smoothing to control the geometry of generated walls while preserving original surfaces.
- Created tests to validate the functionality of the new symmetry features against baseline geometry.
- Updated existing assets and node groups to support the new symmetry capabilities without introducing additional dependencies.

tests/tools/nodes/test_arrangement.py

@@ -98,7 +98,8 @@ def _surface(node_group):
     image.pixels.foreach_set(pixels.ravel())
     values = {"Subdivide": 1, "Thickness": 0.2, "Depth Image": image,
               "Uniform Scale": 1.0, "Reference Depth": 2.5, "Depth Scale": 0.8,
-              "Smooth": 1, "Normal Smooth": 2, "Depth Split": 0.25}
+              "Smooth": 1, "Normal Smooth": 2, "Depth Split": 0.25,
+              "Depth Offset": 0.5}
     mode = None
     for item in node_group.interface.items_tree:
         if item.item_type != "SOCKET" or item.in_out != "INPUT":