Fail CI loudly when init.sql seeding fails

The "Apply graphitron-sakila-db init.sql" step in .github/workflows/rewrite-build.yml runs psql -f init.sql with no -v ON_ERROR_STOP=1. psql exits 0 when individual statements fail, so a broken or partially-applied init.sql seeds an incomplete schema and the step reports success. The failure then surfaces one step later as the cascade .claude/web-environment.md already documents at length: UnclassifiedType / NoSuchElement / table … could not be resolved in the jOOQ catalog across every pipeline test that touches the missing fixture, with nothing pointing at the seed.

That cascade has cost real time before. .claude/web-environment.md records a stale sandbox DB as a now-eliminated cause of it (the session hook reseeds on every start), and one earlier item’s Done review recorded chasing exactly this shape before finding the DB was missing that item’s new fixtures. CI’s seeding step is the one remaining place the same class of failure can pass silently.

The fix is one flag on the psql invocation, plus a check that the failure mode it produces is readable. Verified 2026-08-04 that today’s init.sql applies cleanly from scratch under -v ON_ERROR_STOP=1 against an empty database, so the flag is a no-op on the current file: this is pure hardening for the next fixture-table addition, not a fix for a live break.

Worth checking two neighbours in the same pass, since they share the failure mode rather than the mechanism:

Filed out of the @node inference work, which added four fixture tables to init.sql and noticed the seeding step would not have caught a typo in them.