Docker Networking IPv6: Enable LLAs Without "--subnet"

It would be incredibly useful in the network modeling world if we could create a new docker network (driver can be anything) with IPv6 enabled, but without specifying a subnet. The basic idea should be that the containers attached to this new network would automatically get their LLAs, but would not receive a GUA of any sort.

The main use case for this is creating a virtual point-to-point network between two containers (eg: Arista cEOS containers, or FRR containers, etc). Their respective interfaces would not be configured with an IPv4 or IPv6 GUA of any sort, just an LLA. These containers can form peers with one another via their LLAs using IPv6 ND, without any other address assignments required.