Refactor depth surface handling and unify depth sampling rules

- Removed the `always_vertex` parameter from `build_surface_camera` to streamline depth sampling for cutouts and ensure consistent behavior across depth plane and panorama.
- Updated depth sampling logic to ensure that all free boundary points, including the original frame of the depth plane, use neighboring face depth instead of their own texture sampling.
- Adjusted the depth mask deletion process to operate on faces rather than points, eliminating the need for additional cleanup of dangling edges.
- Ensured that the cutout rules are consistently applied across all relevant nodes, removing exceptions and simplifying the logic.
- Updated tests to verify the new behavior, ensuring that cutout points follow the depth of adjacent faces and that the original frame maintains its depth sampling.
- Refactored geometry handling in multiple depth-related nodes to improve clarity and maintainability.

tools/nodes/groups/image_layer.py

@@ -19,7 +19,7 @@ def build_image_layer_group():
     input_sockets.insert(4, ('Object Space', 'NodeSocketBool'))
     input_sockets.insert(2, ('Alpha Fix', 'NodeSocketFloat'))
     options = interface.new_panel(name='Options', default_closed=True)
-    option_names = {'Alpha Fix', 'Normal Scale', 'Object Space'}
+    option_names = {'Alpha Fix', 'Object Space'}
     for name, socket_type in input_sockets:
         socket = interface.new_socket(name=name, in_out='INPUT', socket_type=socket_type, parent=options if name in option_names else None)
         if name in {'Alpha', 'Alpha Fix'}: