refactor(kernel): number profile loops once and record face history as faces are built

One numbered loop type (crate::numbered) carries each segment's profile
numbers through orientation, snapping, circle re-seaming, re-sampling and
rotation; every builder orients its regions through it once. Builders that
make their own side faces pair each face with its provenance as it is made
(ruled walls by the wire edges each face holds, smooth lofts, coils and path
sweeps by segment), and cap_and_close appends the caps itself. Column
following is kept only for faces truck sweeps internally (rsweep, tsweep
along paths, cones, where an apex vertex stays put). Extrude derives face
sources and history in one topology pass. One attach entry point takes
operands with their edges already indexed.

Geometry, face order, face sources and recorded origins are unchanged.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01J53sR6gEaVt56soFDpTck8

crates/kernel/src/emboss.rs

@@ -1,7 +1,9 @@
 //! Exact radial embossing of orthogonal profiles on complete cylindrical walls.
 use crate::body::{Body, Solid, from_p3, p3};
 use crate::history::Change;
+use crate::numbered::NumberedRegion;
 use crate::offset::{Surf, surf_of};
+use crate::record::Operand;
 use crate::{KernelError, Result, guard};
 use solvecraft_geom::{Loop2, Plane, Region2, Seg2, Vec2, Vec3};
 use truck_modeling::{self as mt, Transformed, builder};
@@ -255,7 +257,6 @@ fn emboss_impl(body: &Body, anchor: Option<Vec3>, plane: &Plane, regions: &[Regi
         let s0 = (plane.origin - o).dot(tangent);
         let map2 = |p: Vec2| Vec2::new(s0 + plane.dir_to_world(p).dot(tangent), z0 + plane.dir_to_world(p).dot(axis));
         let mut count = 0usize;
-        let mut mapped = Vec::new();
         // The regions mapped onto the wall as given (their loops' turning may differ from the
         // sketch's): profile numbering follows them.
         let mut unoriented = Vec::new();
@@ -294,12 +295,11 @@ fn emboss_impl(body: &Body, anchor: Option<Vec3>, plane: &Plane, regions: &[Regi
                 }
                 loops.push(Loop2 { segs });
             }
-            let outer = loops.first().ok_or_else(|| fail("profile"))?.ccw();
-            let holes = loops.iter().skip(1).map(|l| l.ccw().reversed()).collect();
-            mapped.push(Region2 { outer, holes });
             let mut given = loops.into_iter();
             unoriented.push(Region2 { outer: given.next().ok_or_else(|| fail("profile"))?, holes: given.collect() });
         }
+        let numbered: Vec<NumberedRegion> = crate::numbered::number_regions(&unoriented).iter().map(NumberedRegion::oriented).collect();
+        let mapped: Vec<Region2> = numbered.iter().map(NumberedRegion::region).collect();
         validate_profiles(&mapped, tol)?;
         if qualify {
             let segment = mapped.first().and_then(|region| region.outer.segs.first()).ok_or_else(|| fail("empty profile"))?;
@@ -343,16 +343,13 @@ fn emboss_impl(body: &Body, anchor: Option<Vec3>, plane: &Plane, regions: &[Regi
         // History of the faces added (walls from their profile segments, the raised or sunk
         // region the profile's end cap), in the order added.
         let mut added_history = Vec::new();
-        let mut origins = crate::record::loop_origins(&unoriented).into_iter();
-        for reg in &mapped {
+        for reg in &numbered {
             let mut cap = Vec::new();
-            for (li, lp) in std::iter::once(&reg.outer).chain(&reg.holes).enumerate() {
+            for (li, numbered_loop) in reg.loops().enumerate() {
+                let lp = &numbered_loop.lp;
                 let (base, top, walls) = wrapped_loop(lp, r, rr, &at)?;
-                let loop_origins = origins.next().ok_or_else(|| fail("profile numbering"))?;
-                if loop_origins.len() != walls.len() {
-                    return Err(fail("profile numbering"));
-                }
-                added_history.extend(loop_origins.iter().map(|o| crate::record::profile(o)));
+                // One wall per segment, in order.
+                added_history.extend((0..walls.len()).map(|j| crate::record::profile(numbered_loop.numbers(j))));
                 if li == 0 {
                     footprints.push((lp, base.inverse()));
                 } else {
@@ -383,7 +380,7 @@ fn emboss_impl(body: &Body, anchor: Option<Vec3>, plane: &Plane, regions: &[Regi
         // gathered: the other faces kept, the wall's pieces left around the footprints (split
         // when the profile's holes leave more than one), then the faces added.
         let pieces = if base_patches.len() > 1 { Change::Split } else { Change::Modified };
-        let mut history: Vec<_> = (0..faces.len()).filter(|i| *i != fi).map(|i| crate::record::from_face(0, i, Change::Kept)).collect();
+        let mut history: Vec<_> = crate::record::kept_except(faces.len(), fi).collect();
         history.extend(std::iter::repeat_n(crate::record::from_face(0, fi, pieces), base_patches.len()));
         history.extend(added_history);
         for patch in base_patches {
@@ -395,7 +392,7 @@ fn emboss_impl(body: &Body, anchor: Option<Vec3>, plane: &Plane, regions: &[Regi
         if !result.validity().is_empty() {
             return Err(fail("rebuilt cylinder is not a closed manifold"));
         }
-        Ok(EmbossOutcome::Body(crate::record::attach(result, &[body], history)?))
+        Ok(EmbossOutcome::Body(crate::record::attach(result, &[Operand::new(body)], Some(history), Default::default())?))
     })
 }