Live docs point into the corpus BY DATE -- "see `decisions.md` 2026-07-10" --
about 32 such references across 12 files, plus the same form in historical issue
comments. The split would dangle every one of them.
Each stripped file now ends with a generated "Records formerly in this file"
index: date, title, and a link to the record's new path. A reader following a
date pointer lands on the file it names and resolves from there. That is far
cheaper and less error-prone than rewriting 32 references by hand, and it also
covers the issue-comment breadcrumbs, which cannot be rewritten at all.
Caught while verifying it: the generated `## Records formerly in this file`
heading is itself an H2, so the record parser counted one legacy-unmigrated
record per stripped file -- the notice went 0 -> 6. Same treatment as the
existing `## Index` section: skip it by name. SKIP_HEADINGS moved to
decisions_lib as the single source of truth, since three modules now need it.
Found by reading the validator's notice output on a trial migration, not by
inspection -- the corpus still validated OK, so nothing else would have flagged it.
timothy
64b65fd2db