descriptorRadioList does not honor DescriptorVisibilityFilter extensions.

The workaround for this has been to pass an already filtered list of descriptors to descriptorRadioList (ie here):

f.descriptorRadioList([...], descriptors: h.filterDescriptors(app, MyExtensionPoint.all()))

However this has a side effect as descriptorRadioList is using an index to match frontend selected descriptor with a backend instance, so when a descriptor is hidden (by the visibility filter) in the frontend then backend indexes do not match.

So, I believe descriptorRadioList should be fixed to either a) Generate correct indexes when there a visibility filter or b) stop using indexes to match things (which seems quite awkward).