Support Xarray Datasets and DataArrays in `cubed.visualize`

[tomwhite]

I don't think there's currently a way of visualizing datasets in a single diagram, so this would be very handy.

[tomwhite]

Current workaround:

cubed.visualize(*(ds[var].data for var in ds.data_vars.keys()))

[TomNicholas]

Maybe just define an Xarray accessor in cubed-xarray so that you can do ds.cubed.visualise?

https://docs.xarray.dev/en/stable/internals/extending-xarray.html

[tomwhite]

Maybe just define an Xarray accessor in cubed-xarray so that you can do ds.cubed.visualise?

https://docs.xarray.dev/en/stable/internals/extending-xarray.html

Thanks for the suggestion @TomNicholas - I didn't know about this extension point! I have implemented it in cubed-dev/cubed-xarray#22 and it has been working well for me.