Test suites were running DELETE FROM.../deleteMany() against whatever
DATABASE_URL pointed to, which was the live app database, wiping user
credentials and library. Add a guard in both the worker conftest and
web test setup that raises before any cleanup unless the target DB
name ends in '_test'. Default DATABASE_URL to lyra_test when unset in
the worker, and make `npm test` target lyra_test explicitly.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Jonathan