ENH: improve boxlib data type detection

[yut23]

PR Summary

Make CastroDataset and MaestroDataset inherit from AMReXDataset so they supercede it when calling yt.load. This allows loading output files from those projects without needing to pass hint.

I don't personally use Nyx, WarpX, or Orion, so any input from those projects would be appreciated.

PR Checklist

• New features are documented, with docstrings and narrative docs
• Adds a test for any bugs fixed. Adds tests for new features.

[yut23]

Some of the Castro (and Maestro) sample datasets are from before we migrated from BoxLib to AMReX, so the job_info files don't contain the string "amrex". That means CastroDataset and BoxlibDataset are valid candidates for yt.load, but AMReXDataset is not. This exposed a fun edge case in find_lowest_subclasses, where it would add AMReXDataset to the list of candidates.

[neutrinoceros]

Thank you for tackling this long standing problem with the boxlib frontend !

This seems fine to me as a non-expert of this frontend (and the codes it relates too), but I'd very much like @zingale's opinion on this (or possibly recommendations for any other boxlib experts).

I think we should also clearly state how the inheritance hierarchy is designed: is it reflecting how the supported codes relate to each other ? is it a pure abstraction aiming for maximal code reuse ? is it purely historical ? anything else ?

[zingale]

I will test this today (and I can test Nyx). @ax3l can you test WarpX on this PR?

[zingale]

I've confirmed that this works with Nyx, Castro, and MAESTROeX without needing to use the hint keyword

[neutrinoceros]

@yut23 can you cleanup the branch history ? It looks like the first commit is only made of changes that were incorporated already

[neutrinoceros]

I actually think the change is small enough that we don't need too much extra manual validation. I'll give @ax3l an other week or so to tune in if he wants but otherwise I think I'll just merge this.