One-time script (dry-run default, --apply in a transaction, idempotent) that maps
every party-ceiling override (another/same dwelling or premises above) currently
stored as an external roof value onto the party-ceiling member, reusing the live
roof_party_ceiling_guard so the backfill and the classifier cannot drift. Updates
property_overrides (TEXT, the modelling read path) and the roof classifier cache;
dry-run against the audited DB reports 106 rows. No FE migration — the party-
ceiling values already exist in the roof pgEnum.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
