Refactor Cutout and Image Editing Logic

- Renamed "Base Plane Depth" to "Reference Depth" across validate_cutout.py for consistency.
- Introduced a new specification for Cutout mesh sampling to ensure source pixel spacing is preserved and limits are applied correctly.
- Unified naming conventions for image editing results to maintain consistency across Remove Background, Upscale, and Crop operations.
- Updated the handling of Refine Selection to ensure it retains the original bounds and does not apply unnecessary cropping.
- Enhanced material generation logic to connect image color directly to IOR Level, improving the rendering of dark areas.
- Established clear requirements for geometry depth controls and image result materials to ensure consistent behavior across different components.
- Removed outdated logic and ensured all changes are documented and tested for regression.

tools/node_assets/validate_cutout.py

@@ -140,7 +140,7 @@ def main():
         "Smooth Iterations",
         "Cleanup",
         "Smooth",
-        "Base Plane Depth",
+        "Reference Depth",
         "Depth Direction",
         "Uniform Scale",
         "Depth Image",
@@ -153,7 +153,7 @@ def main():
             "Thickness",
             "Depth Scale",
             "Double Sided",
-            "Base Plane Depth",
+            "Reference Depth",
             "Depth Direction",
             "Uniform Scale",
             "Depth Image",
@@ -162,7 +162,7 @@ def main():
             "Geometry",
             "Thickness",
             "Depth Scale",
-            "Base Plane Depth",
+            "Reference Depth",
             "Uniform Scale",
             "Depth Image",
         ],
@@ -184,7 +184,7 @@ def main():
         "Thickness": set(shapes.CUTOUT_SHAPES),
         "Depth Scale": {"DEPTH_BALLOON", "DEPTH_SURFACE"},
         "Double Sided": {"DEPTH_BALLOON"},
-        "Base Plane Depth": {"DEPTH_BALLOON", "DEPTH_SURFACE"},
+        "Reference Depth": {"DEPTH_BALLOON", "DEPTH_SURFACE"},
         "Depth Direction": {"DEPTH_BALLOON"},
         "Uniform Scale": {"DEPTH_BALLOON", "DEPTH_SURFACE"},
         "Depth Image": {"DEPTH_BALLOON", "DEPTH_SURFACE"},
@@ -347,7 +347,7 @@ def main():
         ("Depth Image", point_image),
         ("Depth Scale", 1.0),
         ("Uniform Scale", 1.0),
-        ("Base Plane Depth", 2.0),
+        ("Reference Depth", 2.0),
         ("Depth Direction", (0.0, 0.0, 1.0)),
     ):
         set_modifier_input(
@@ -398,7 +398,7 @@ def main():
         ("Depth Image", point_image),
         ("Depth Scale", 1.0),
         ("Uniform Scale", 1.0),
-        ("Base Plane Depth", 2.0),
+        ("Reference Depth", 2.0),
         ("Smooth Iterations", 0),
     ):
         set_modifier_input(