Runs typecheck, lint, and build on every push to main and on pull requests.
Targets the self-hosted Gitea Actions runner (crispygoat-host-runner)
using labels [self-hosted, linux, ubuntu-latest].
Uses the local dev stack endpoints (PostgREST on :3001, MinIO on :9000,
Postgres on :5432) for env vars so no secrets need to be wired in.
