#917 Purge: root clutter, Jenkins, GitHub workflows, SonarQube, Dockerfile.production, helm, ansible, systemd, dead enterprise/sandbox

EARS SPEC: - The repository shall contain no Jenkinsfile, .github/workflows, SonarQube config/scripts, helm/, ansible/, systemd units, Dockerfile.production, or root one-off scripts/review docs. - The repository shall not contain enterprise/sandbox nor /internal/sandbox routes. - The tool-name set before and after shall be identical except for intentionally removed tools. Parent epic: #913. Synthesis (technical problems / solution domains / alternatives) recorded as a comment when started.