Why: The new confirmation table is additive, and the compatibility ledger must name that fact or the store suite rejects the schema.
Evidence: SELF go test ./internal/store/ -run TestMigrationCompatRegistered passed after the registration.
Impact: Old readers keep their current floor. They do not need to understand human decision rows.
Refs: W4b human confirmation design r1
Co-authored-by: Cursor <cursoragent@cursor.com>