Self-deleting script auto-migrates Claude Code model before shutdown

A developer created a launchd job that automatically updates Claude Code's settings.json to switch from the Fable 5 model to Opus before Fable 5 shuts down on July 7, 2026. The script includes a date guard, jq-based model replacement, a notification, and self-destructs by unloading its own plist after execution. This ensures a one-time migration without leaving behind a recurring no-op job.