Generates production-ready GitHub Actions workflows, custom actions, and CI/CD configurations following security and performance standards. Creates CI/CD pipelines, test workflows, deployment configurations, matrix builds, caching strategies, composite actions, Docker actions, JavaScript actions, and reusable workflows. Use when creating or scaffolding GHA resources, writing .github/workflows YAML files, setting up build automation, implementing deployment pipelines, adding security scanning, or building reusable actions — including triggers like 'create a workflow', 'build a pipeline', 'add CI', 'set up GHA', or 'generate a YAML workflow'.