Add new functionality for image rectification and depth metadata handling

- Implemented a preview tool for rectifying images with interactive aspect controls in `preview.py`.
- Added tests for depth metadata loading to ensure consistent schema usage in `test_depth_metadata.py`.
- Developed comprehensive tests for cutout calibration processes in `test_cutout_calibration.py`, including stability checks and depth calibration.
- Created tests for frame compositing operations in `test_frame_compositing.py`, ensuring correct handling of depth and transparency.
- Introduced material slot inheritance functionality in `material_slots.py` to manage geometry material assignments.
- Built shared shader nodes for material processing in `shader.py`, including roughness and bump mapping setups.

tools/nodes/groups/image_relief_plane.py

@@ -29,6 +29,7 @@ def build_image_relief_plane_group(image_plane_group):
     geometry = _interface_socket(group, "Geometry", "INPUT", "NodeSocketGeometry")
     geometry.structure_type = "SINGLE"
     subdivide = _interface_socket(group, "Subdivide", "INPUT", "NodeSocketInt")
+    subdivide.description = "Increase mesh density to represent finer shapes. Higher levels create more vertices and require more processing time."
     subdivide.default_value = 6
     subdivide.min_value = 0
     subdivide.max_value = 10
@@ -36,11 +37,12 @@ def build_image_relief_plane_group(image_plane_group):
     thickness.default_value = 0.5
     thickness.min_value = 0.0
     thickness.subtype = "DISTANCE"
-    thickness.description = "Fixed relief base thickness"
+    thickness.description = "Set the thickness of the flat base beneath the relief."
     depth_scale = _interface_socket(group, "Depth Scale", "INPUT", "NodeSocketFloat")
     depth_scale.default_value = 0.5
     depth_scale.min_value = 0.0
     smooth = _interface_socket(group, "Smooth", "INPUT", "NodeSocketInt")
+    smooth.description = "Set the number of mesh smoothing passes. Higher values smooth the surface more but may soften details. Zero disables smoothing."
     smooth.default_value, smooth.min_value, smooth.max_value = 0, 0, 20
     options = group.interface.new_panel(name="Options", default_closed=True)
     base_plane_depth = _interface_socket(
@@ -53,7 +55,7 @@ def build_image_relief_plane_group(image_plane_group):
     base_plane_depth.default_value = 1.0
     base_plane_depth.min_value = 0.0
     base_plane_depth.subtype = "DISTANCE"
-    float_input(group, "Smooth Weight", 1.0, maximum=1, subtype="FACTOR", parent=options)
+    float_input(group, "Smooth Weight", 1.0, maximum=1, subtype="FACTOR", parent=options).description = "Control the strength of each mesh smoothing pass. Higher values move vertices more."
     vector_input(group, "Depth Direction", (0, 0, 1), subtype="DIRECTION", parent=options)
     data = group.interface.new_panel(name="Data", default_closed=True)
     uniform_scale = _interface_socket(