If I understand correctly, one consideration for the location of the MMS test TOML inputs could be that we might want to test whether the inputs are valid on CI, by running them for 1 timestep, like the TOML in examples/. Currently it looks like many of the MMS test inputs in the runs/ directory have become out of date following the various input namelist changes.

BTW all the documentation builds seem to be broken at the moment - there is some error about a missing get_cmap function when loading PyPlot. I don't think it's anything we've done, and I can't reproduce it on my laptop, so I'm hoping it goes away with some package updates (unless anyone wants to dig into it, e.g. excluding the version of PyPlot that it's currently trying to use so it falls back to the previous one?).