Docker CLI reference covering containers, images, Compose, volumes,
networks, troubleshooting, and Dockerfile optimization. Placed in
optional-skills/devops/ since it's a documentation-only skill with
no external dependencies beyond Docker CLI.
Based on PR #3032 by @sprmn24. Moved from skills/ to optional-skills/
and trimmed the description to be concise.
Co-authored-by: sprmn24 <sprmn24@users.noreply.github.com>