X_DOC_MIGRATION_COUNT_STALE

a wiki/Upgrading.md count is not the count of the section it names

three shapes, one code: a row claiming a number that major's own CHANGELOG.md section does not hold, the aggregate row disagreeing with the sum of the per-major rows, and a released major from 2.0.0 on with no row at all. The count used to be derived from the WHOLE file, which cannot see a migration filed under the wrong heading — a misplaced entry only makes the number smaller

bun run scripts/changelog-check.ts --json — each finding carries the number that section actually holds; write that number into the cell, or add the missing row