Read region sources of associative surfaces by edge

A swept, extruded, revolved or lofted surface made from a region now
reads the region through one geometry dependency per edge, each naming
its edge by a persistent subentity id recorded in the drawing's
subentity manager, so the surface follows the region. A lofted surface
keeps one continuity and bulge value per cross section.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/scene/model/sweep_model.rs

@@ -13,7 +13,7 @@ use codec::EntityType;
 
 use crate::entities::curve::entity_curve;
 pub use super::sweep_command_model::{
-    is_sweep_path, is_sweep_profile, scaled_sweep_path_refusal, spatial_profile, spatial_sweep_record, surface_sweep_record, sweep_expressions, link_sweep_expressions, link_sweep_sources, sweep_sources, SWEEP_SOURCES_APP, resweep_from_sources, surface_associativity, set_surface_associativity, assoc_edge_curve, sweep_record, sweep_refusal_code, sweep_selection_options, swept_surface_entity, swept_with_options,
+    is_sweep_path, is_sweep_profile, scaled_sweep_path_refusal, spatial_profile, spatial_sweep_record, surface_sweep_record, sweep_expressions, link_sweep_expressions, link_sweep_sources, sweep_sources, SWEEP_SOURCES_APP, resweep_from_sources, surface_associativity, set_surface_associativity, assoc_edge_curve, assoc_source_supported, region_edge_curves, AssocCurve, sweep_record, sweep_refusal_code, sweep_selection_options, swept_surface_entity, swept_with_options,
 };
 
 /// A drawn profile, as the kernel wants it: the plane it lies in and the