Define a discrete list of features representing "support" (capability manifest)

[clbarnes]

Not to blow my own trumpet, but I'm trying to get capability manifests into shape for Zarr and OME-Zarr; it could be used for spatialdata too.

This could be used to inform a set of conformance tests.

Even coverage of a subset e.g. "ome-zarr/v0.6/coordinate_transformations/*/{forward,reverse}" would be a good start.