Move GraphPES to external Model Posture

[CompRhys]

@jla-gardner Can we upstream this interface like the other models?

[CompRhys]

I am leaning towards removing graphPES entirely as something that is wrapped in the main repo because unlike the other wrappers we have at top level there is not an obvious "foundation"-level model unique to the framework that we might want to make the obvious connection for users. Thoughts?

[craigxchen]

Are you still leaning towards just removing it? Do we want to add any deprecation warning or just take it out of everything?

[CompRhys]

I would favor relocating this code to the package and then purging it here. There's a balance to strike and whilst graphPES is a nice framework it is one amongst many trying to wrestle order from lots of different MLIP packages. The other models wrapped are individual tied to individual near SOTA MLIPs.

The upstream should be merged before we reap here.

[craigxchen]

Opened the upstream PR, can follow up with removal here whenever that gets merged

[CompRhys]

I think we can actually just proceed and remove here and remove the tutorial and CI specific stuff if you want to make that PR.

[orionarcher]

I'm in favor of removing