Every section banner dies (103 -> 0) across test/lang, the observer
suites, the C carriers, and the five comment-heavy corpus fixtures;
banner provenance (#N cites, carrier numbers, repair-cluster labels)
folded into headers or adjacent WHY comments. Narration deleted; row
provenance, ref cites, divergence pins, and layout contracts kept
(fwd-ref decl-order guards and bootstrap-gate corpus rationale
restored where the sweep over-cut). Comment-only proven: all 3742
wwbuild workdir .s byte-identical before/after; test-commit and
test-byteid (161 lang + 1399 data, 0 pinned-divergent) green.
test/xmod/m1_test.ww replaces 989_m1mangle_run.c and
989_m1usehint_run.c with every assertion preserved (5 tree rows +
2 usehint rows, both stages, plus the leaf_collision byte-id leg;
concat order strengthened from shell glob to byte-sorted listdir).
