These env vars (DB_*, AUTH_*, DOCKER_*, etc.) are all runtime
configuration provided by users when running the Docker container.
They don't influence the build output since Next.js standalone mode
reads process.env at runtime and SKIP_ENV_VALIDATION=true skips
validation during build. Listing them in build.env caused unnecessary
cache busting in local dev.
Also restores coverage report comments per review feedback.
Thomas Camlong
33280a2059