Sheet metal: rules as expressions (Thickness, K-factor, bend radius, reliefs, gaps; may use parameters), sheet bodies kept as flat patterns and sewn folded from exact faces (new kernel::sew), Flange (base, edge with height to the outer face, angle, inside/outside/middle, several edges at once with corners closed to the rule gap, contour from an open chain), Hem, Unfold/Refold with cut-outs that follow the bends, Convert to Sheet Metal, flat pattern with bend lines and bend table, DXF export; recipes: sm_flange, sm_hem, unfold/refold, rule edits (oracle 67-76 all pass)

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

crates/doc/src/assembly.rs

@@ -187,6 +187,9 @@ impl FeatureKind {
                 dir(direction);
             }
             FeatureKind::Thread { face, .. } => pt(face),
+            FeatureKind::SheetFlange { edges, .. } | FeatureKind::SheetHem { edges, .. } => edges.iter_mut().for_each(pt),
+            FeatureKind::SheetConvert { face, .. } => pt(face),
+            FeatureKind::SheetBase { .. } | FeatureKind::SheetContour { .. } | FeatureKind::SheetUnfold { .. } => {}
             FeatureKind::Coil { base, axis, .. } => {
                 pt(base);
                 dir(axis);