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/lib.rs

@@ -39,6 +39,7 @@ mod loopblend;
 mod measure;
 mod mesh_convert;
 mod meshbody;
+mod numbered;
 mod offset;
 mod ops;
 mod polybool;