Implement arrangement framework for node groups

- Introduced `frames.py` to manage field complex calculations and their arrangement within node groups.
- Added functionality to create and remove field frames based on node arrangements.
- Developed `passages.py` to find unobstructed paths for connections around calculation frames.
- Implemented `references.py` to route shared results on peripheral tracks, ensuring efficient distribution of outputs.
- Created `sections.py` to reserve space for field calculations adjacent to geometry consumers.
- Added `sources.py` to position shared calculation sources effectively beside their distribution channels.
- Enhanced outline smoothing with `outline_smoothing.py` to adapt camera depth along original outlines.

src/anyimage/properties.py

@@ -209,7 +209,7 @@ def cutout_generate_normal_property():
 def cutout_alpha_threshold_property():
     return bpy.props.FloatProperty(
         name="Alpha Threshold",
-        description="Minimum Alpha kept in the Cutout contour",
+        description="Minimum Alpha kept in the Cutout outline",
         default=0.9,
         min=0.0,
         max=1.0,