If STIRLING_PDF_TEST_COVERAGE is set and build/jacoco/jacocoagent.jar is missing, attempt to restore it by running gradlew copyJacocoAgent -PnoSpotless and only enable Cucumber JaCoCo coverage if the agent is present; otherwise emit a warning. Also set stop_grace_period: 1m for the stirling-pdf service in the coverage docker-compose override to allow a cleaner shutdown during coverage runs.