Boundary Fill (SurfaceSculpt): solids from the cells tool bodies enclose (inside some tools, outside the rest), each picked by a point, as new bodies or joined/cut/intersected, tools optionally removed

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01AS5Tn3xieewUSg3uxrMVdL

crates/doc/src/assembly.rs

@@ -216,6 +216,7 @@ impl FeatureKind {
                 dir(direction);
             }
             FeatureKind::Lip { face, .. } => pt(face),
+            FeatureKind::BoundaryFill { cells, .. } => cells.iter_mut().for_each(pt),
             FeatureKind::Rest { position, direction, along, .. } => {
                 pt(position);
                 dir(direction);