Enhanced `.drone.yml` to enable Docker BuildKit for efficient builds and added support for Gradle cache persistence across runs. Introduced OCI-compliant image labels for traceability. Updated `.dockerignore` to exclude unnecessary files from Docker context.
Integrate JaCoCo to enforce and report test coverage with a minimum threshold of 65%. Update Drone CI configuration to use a new Docker registry (rubble.se:5000) and add support for authentication with secrets.
