- lighthouse:after_create/update/delete also declare
Before(gorm:commit_or_rollback_transaction); an After-only anchor put
them past GORM's own commit, so a plain gdb.Create enqueued its
broadcast job after the commit on the pool (deferred from 11-05)
- lighthouse gets the testcontainers Postgres harness and TestBroadcastTx
(commit publishes once, rollback nothing, single-statement write
enqueues on its own transaction, failed write enqueues nothing)