Agent Skills: gh-cli

Standardize all GitHub interactions via the GitHub CLI (`gh`) instead of ad-hoc URLs, UI clicks, or direct REST API calls. Use when you need to read or change GitHub state (repos, issues, pull requests, reviews, check status, Actions workflows/runs, releases, labels, milestones, discussions, gists) and want deterministic output (prefer `--json` + `--jq`). Also use when the user provides a GitHub URL, including deep links like `https://github.com/OWNER/REPO/pull/123`, `.../issues/123`, `.../pull/123/files`, or comment permalinks like `#issuecomment-...`, and you need to fetch the underlying PR/issue/thread and reply. Fall back to `gh api` only when there is no first-class `gh NOUN VERB` command.