Support fixed IP addresses for nodes

[priteau]

Add support for optional fixed IP addresses via opentofu variable control_ip_addresses and parameter ip_addresses for compute and login node groups.

Example:

cluster_networks = [
    {
        network = "foo"
        subnet = "bar"
    }
]
control_ip_addresses = {
   foo = "192.168.0.10"
}
login = {
    interactive = {
        nodes = ["login-0"]
        ...
        ip_addresses = {
            foo = ["192.168.0.20"]
        }
compute = {
    standard = {
        nodes = ["standard-0", "standard-1"]
        ...
        ip_addresses = {
            foo = ["192.168.0.30", "192.168.0.31"]
        }
}

Closes #642.

[sjpb]

Actually this isn't right - logic should be that iff the network key isn't in the map, we default to null, rather than the condition being that the map is empty. So its probably a lookup not a ternary.

[sjpb]

LGTM

[sjpb]

Tested on smslabs. Works. Correct IPs set in metadata on all nodes. site playbook running ok.

[bertiethorpe]

LGTM

Stale