Registering Self-generated IPv6 Addresses using DHCPv6
This is still a draft, but we should consider doing it if it is not challenged during the IETF process. I was present during the discussion at IETF and asked - it seems the DHCP server has to do very little, just accept the information from a v6 client and log the information about the client in the leases file.
https://datatracker.ietf.org/doc/draft-wkumari-dhc-addr-notification/