openssh unix dev - Oct 2023 - sftp: check-file-* extension

Hi,

I wondered if there had ever been consideration to implementing
check-file-handle / check-file-name in OpenSSH's sftp server? While
it's only specified in an expired draft[1] some other implementations
do support it.

[1]:
https://datatracker.ietf.org/doc/html/draft-ietf-secsh-filexfer-extensions-00#section-3