ACL allow specifying CIDRs

[maikelmertens]

Currently, it seems like ACLs in Netbird allow us to specify only groups.

In my scenario, I have a peer acting as a relay, exposing multiple network routes on a remote network. I'd like to restrict access for a specific group (e.g., "devs") to only a subset of this remote network (e.g., only to the DEV subnets) by specifying network ranges/CIDRs.

[Horus-K]

I also hope to add this feature, which will completely crush headscale

[szzylph]

赞成增加该功能！