Agent Skills: gh-project-workflow

End-to-end GitHub execution workflow for project delivery: create project items, assign available single-select fields (such as Status and optional Area), convert draft items to issues when needed, create and check out development branches via `gh issue develop`, then commit, push, create/merge pull requests, and run deployment commands on request. Use when the user explicitly asks to operate GitHub issue/PR lifecycle, or when another repo workflow skill delegates the GitHub tracking and delivery steps to it.