Database migrations CI on GitHub Actions

Every test run replays the full migration history from an empty database.

Why it happens

The test database is created from scratch instead of from a cached schema snapshot.

What to change

1. Dump the migrated schema once and load it directly in test jobs
2. Use --keepdb or the equivalent so the database survives between runs
3. Run migrations against a tmpfs-backed database for speed
4. Test the migration path itself in a separate, less frequent job

Database migrations on runnerhut

jobs:
  test:
    runs-on: runnerhut-4vcpu-ubuntu-2404
    services:
      postgres: { image: postgres:17, env: { POSTGRES_PASSWORD: postgres } }
    steps:
      - uses: actions/checkout@v4
      - run: psql -f schema.sql
      - run: npm test

The only runnerhut-specific line is `runs-on: runnerhut-4vcpu-ubuntu-2404`. Everything else is standard GitHub Actions — the same actions, the same secrets and the same permissions model you use today.