Finalizes work by ensuring everything is committed, pushed to the remote, and reflected on GitHub: closes issues, posts summary comments, and presents a completion table. Use when the user says 'ship it', 'push GH', 'close GH', or 'wrap up'. This is the fallback of last resort — use it for any stack with no dedicated shipping-work-* variant (Go, Rust, TypeScript, Java, and anything else unlisted).
