Collect supported kwargs for fits in one central place

[alexander-held]

Summary

When looking for supported kwargs for something like pyhf.infer.mle.fit in conjunction with Minuit, I believe that I need to check in three places:

• https://pyhf.readthedocs.io/en/v0.6.3/_generated/pyhf.infer.mle.fit.html for model-related configuration,
• https://pyhf.readthedocs.io/en/v0.6.3/_generated/pyhf.optimize.mixins.OptimizerMixin.html for generic minimizer customization,
• https://pyhf.readthedocs.io/en/v0.6.3/_generated/pyhf.optimize.opt_minuit.minuit_optimizer.html for Minuit-specific configuration options (or https://pyhf.readthedocs.io/en/v0.6.3/_generated/pyhf.optimize.opt_scipy.scipy_optimizer.html for scipy).

I believe it could be helpful to have a central place capturing all the possible configuration settings (and default values) for a given setup. I do not really have any idea of how that could be accomplished automatically unfortunately.

The documentation already specifies that kwargs are passed to the optimizer API from infer:

kwargs – Keyword arguments passed through to the optimizer API

and perhaps links here could help users quickly find where to look next.

Documentation Page Link

n/a, see text

Code of Conduct

• [X] I agree to follow the Code of Conduct

[alexander-held]

related: https://github.com/scikit-hep/pyhf/discussions/1832 (hypotest behaves differently)