Run a DHCPv6 client to get a DHCPv6 Prefix Delegation (IA_PD) and assign it to downstream SVIs on EOS.
This uses gNMI interface to Arista to add/delete interfaces.
It will not configure RA parameters since it doesn't appear the EOS supports RA configuration via gNMI.
Not functional, doesn't work, don't try to use it unless you want to write code