networking: module for static names

[vilvo]

Description of changes

• based on decisions to use static names over internal DNS refactor: dns+dhcp to a module, support short host queries #427
• Assumption is that admin-vm: logging module to centralize logs collection #565 depends on this to use hostnames for systems-journal filenames instead of IPs

Checklist for things done

• Summary of the proposed changes in the PR description
• More detailed description in the commit message(s)
• Commits are squashed into relevant entities - avoid a lot of minimal dev time commits in the PR
• Contribution guidelines followed
• Ghaf documentation updated with the commit - https://tiiuae.github.io/ghaf/
• PR linked to architecture documentation and requirement(s) (ticket id)
• Test procedure described (or includes tests). Select one or more:
  • Tested on Lenovo X1 x86_64
  • Tested on Jetson Orin NX or AGX aarch64
  • Tested on Polarfire riscv64
• Author has run nix flake check --accept-flake-config and it passes
• All automatic Github Action checks pass - see actions
• Author has added reviewers and removed PR draft status

Testing

Static names work as expected - guest to guest - but IPs are not statically allocated to support this.
For example:

[ghaf@ghaf-host:~]$ ssh 192.168.101.1

[ghaf@net-vm:~]$ ssh gui-vm
logout
Connection to log-vm closed.

[ghaf@net-vm:~]$ ssh log-vm

[ghaf@gala-vm:~]$ 
logout
Connection to log-vm closed.

[ghaf@net-vm:~]$ ssh gala-vm

[ghaf@log-vm:~]$ 
logout
Connection to gala-vm closed.

[ghaf@net-vm:~]$ ssh chromium-vm

[ghaf@zathura-vm:~]$ 
logout
Connection to chromium-vm closed.

[ghaf@net-vm:~]$ 
logout
Connection to 192.168.101.1 closed.

[ghaf@ghaf-host:~]$ 

IPs also get reallocated over nixes-rebuild ... switches.

[vilvo]

Replaced with PR #584 from collab ghaf-dev fork.