This skill should be used when the user says "execute infra change", "run infra plan", "apply infrastructure change", "execute change", "arn infra execute", "deploy infra plan", "execute infrastructure plan", "run infrastructure change", "apply infra plan", "infra execute", "arn-infra-execute-change", or wants to orchestrate the phased execution of a structured infrastructure change plan, invoking agents for IaC generation, security gates, cost gates, deployment, verification, and review.