remove custom_typing.py

[atravitz]

we don't think this file is needed anymore https://github.com/OpenFreeEnergy/openfe/blob/main/openfe/utils/custom_typing.py

@dwhswenson do you have any historical knowledge that would indicate we should keep this?

[dwhswenson]

This was mainly intended so that external type names that might not be obvious when reading were given consistent type aliases. Best example is rdkit.Chem.rdmol.Mol: no one wants to type that over and over, and Mol alone is unclear if you might be working in RDKit or OEChem or others. So the intent was to standardize on the alias RDKitMol.

In the end, I'm not sure how often we need typing from these external packages -- at least, a lot of that should probably be happening within tools that OpenFE imports. So maybe enforcing that consistency isn't as valuable. Since this is only typing, the only problems you'll have in removing this file will be things that import from here to use these names. You'll find a few, but they should be easy to fix.

[atravitz]

I found that the only place that custom types are used is in network plotting, so custom_typing will live in konnektor as of OpenFreeEnergy/konnektor#182.

I'm open to adding custom types back in where they're helpful, but I think this conversation can be considered resolved when #1522 is merged.

[mikemhenry]

Like the network viz stuff, I think the custom typing makes the most sense in gufe (we can probably leverage the aliases more)