Add new onboarding strategy

[damyan]

Summary

Currently, the metal plugin onboards (i.e. creates Endpoints) only for known inventories from a static list. See https://github.com/ironcore-dev/FeDHCP?tab=readme-ov-file#configuration-5.

Basic example

Enhance the inventory configuration to a more comprehensive format. Example:

namePrefix: server-
hosts:
  - name: machine-1
    macAddress: aa:bb:cc:dd:ee:ff
  - name: machine-2
    macAddress: 11:22:33:44:55:66
macPrefixFilter:
  - aa:aa:aa:aa:aa:aa
  - bb:bb:bb:bb:bb:bb

Onboarding algorithm:

• if a static hosts section exists, onboard only those inventories (matches current behaviour)
• if no static hosts section exists, onboard the inventories with MAC addresses matching the macFilter, according to the following naming scheme:
  • if a namePrefix section exists, each inventory shall get a suffix-generated name like server-abcd, server-uxyz, etc.
  • if no namePrefix section exists, generate the name with the predefined prefix compute, resulting in names like compute-abcd, compute-uxyz, etc.
• if neither hosts nor macFilter section is specified, do not onboard anything. We want a restrictive onboarding approach, though, that might change in the future

Motivation

We want more flexibility:

• we don't (always) want pets as servers, we might as well go on and onboard every available inventory
• we want more flexibility about the naming scheme
• we want to support filtering, a.k.a. onboard inventories matching certain criteria

[damyan]

/cc @afritzler Comments are welcome