Agent Skills: release-skills

Release workflow for baoyu-skills plugin. Use when user says "release", "发布", "push", "推送", "new version", "新版本", "bump version", "更新版本", or wants to publish changes to remote. Analyzes changes since last tag, updates CHANGELOG (EN/CN), bumps marketplace.json version, commits, and creates version tag. MUST be used before any git push with uncommitted skill changes.