Three Phase-4 sub-phases shipped this session (all local-only on main,
1805 tests passing, clippy clean):
- 4a.3 table-level/multi-column CHECK (new __rdbms_playground_table_checks)
- 4b foreign keys in CREATE TABLE (ADR-0013 named relationships)
- 4c DROP TABLE [IF EXISTS] (DropOutcome::Skipped no-op-with-note)
Handoff records the growing 4i deferral list (a–e, canonical in
ADR-0035 §13 4i) and flags the 4d escalation (IndexSchema.unique model
extension for CREATE UNIQUE INDEX).
claude@clouddev1