The weekly release-dry-run schedule failed at 'Resolve rehearsal
metadata' because GitHub does not apply workflow_dispatch input
defaults to schedule events, so rollback_version arrived empty and
resolve_release_promotion.py rejected the run.
Scheduled runs now pass --derive-rollback-latest-stable, which fills
an empty rollback_version with the latest stable tag preceding the
rehearsal version (currently v6.0.4 for 6.0.5-rc.3). Manual dispatches
keep the explicit rollback_version requirement; the stale prefilled
5.1.29 default is removed so operators state the target themselves.
The deployment-installability contract records the scoped scheduled
exception.
rcourtman
7645965afe