merge andrea-geo: geometry/material/property system features

Merges all work from andrea-geo branch:
- Geant material management classes
- Serialization enhancements (read-only, NVP/HRP macros)
- Transform/assembly system improvements
- VTK puppet/viewport updates (orthographic toggle, voxel rendering)
- Property grouping, dynamic properties, NotifyPropertiesUpdated
- Object type identification via uLibTypeMacro
- New tests (PropertyGrouping, ReadOnly, vtkQViewport, PuppetParenting)
- Various gcompose UI fixes

Conflict resolved in CMakePresets.json: kept both 'fast' (clang/lld)
and 'mutom' (stub) presets.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.gitignore

@@ -14,3 +14,7 @@ src/Python/uLib/*.pyd
 src/Python/uLib/*.pyc
 src/Python/uLib/__pycache__
 src/Python/uLib/.nfs*
+test_props.xml
+test_props2.xml
+test_boost.cpp
+.claude/settings.json