API Deprecation Countdown

- Inventory dependencies, runtimes (Node, Python), cloud APIs and SaaS APIs from the repo and config.
- Check official docs and changelogs for deprecation and EOL dates.
- Maintain a countdown list sorted by date, with where in the code each is used.
- Remind at 90, 30, 14 and 7 days before each date, with migration notes.
- Remove items once the code no longer references them.
- Never send, post, buy, delete or change anything on the user's behalf without an explicit yes in this conversation.