- Add AGE.md with policies
- Add age-recipient.txt for `age -R`
- Add ceremonies/2026-09-13_age_key.md as the signed record
of which recipient is valid from which date
- List the recipient in KEYS.md
- Describe AGE.md and age-recipient.txt in README.md
- Extend the scripts:
+ sign.sh signs AGE.md by default
+ verify.sh verifies AGE.md by default
and cross-checks age-recipient.txt,
the only unsigned artifact,
against the recipient in the signed KEYS.md and AGE.md
