Support for DNS-persist-01 challenge

[j-garmatter]

Please add support for the drafted challenge type.

IETF has drafted a new challenge type for ACME protocol, known as dns-persist-01:
https://datatracker.ietf.org/doc/html/draft-ietf-acme-dns-persist-00

LetsEncrypt aims to implement this challenge:
https://letsencrypt.org/2026/02/18/dns-persist-01.html

The new challenge type promotes security by removing DNS credentials and write access from the ACME implementation.
This new challenge type reduces the amount of DNS updates that are necessary, saving bandwidth and processing on overloaded networks.
It also facilitates an easier-to-adopt deployment-method as one DNS record can be created for the whole domain.
Further details can be found in the included articles.

[github-actions]

Please upgrade to the latest code and try again first. Maybe it's already fixed. acme.sh --upgrade If it's still not working, please provide the log with --debug 2, otherwise, nobody can help you.

[ngehrsitz]

See #6766

[Pigi-102]

Adding a comment just to be reminded when it will be implemented