feat: automated weekly skill check against Claude Code changelog

[ryzizub]

Description

Add a bot-driven workflow that automatically checks Wingspan's skills against the latest Claude Code changelog on a weekly cadence. When Claude Code ships changes that affect skill behavior (tool APIs, hook contracts, slash-command semantics, frontmatter conventions), the bot should surface which skills may be impacted so they can be reviewed and updated before they silently break.

Requirements

• Scheduled weekly job (e.g. GitHub Actions cron) that fetches the latest Claude Code changelog/release notes.
• Diff the changelog against the last-checked version and extract entries relevant to skills, agents, and hooks.
• Map changed surfaces to potentially affected skills under skills/ (and agents/, hooks/).
• Output a report — open or update a tracking issue listing impacted skills and the relevant changelog entries.
• No false-quiet: if parsing fails or the changelog format changes, the job flags it rather than passing silently.

Additional Context

Pairs with the evaluation tables/data work so impacted skills can be re-tested against updates automatically. See #200.