[Bug] In Edit tags window, hierarchical tags are not shown at the top

~The feature already exists in Desktop. I think (but not sure) that it should be easy to implement using the new backend.~

~Regardless of whether this is implemented or not, please hide the `Edit tags` option when multiple cards are selected because this option makes sense only when a single card is selected.~

The actual issue is described in https://github.com/ankidroid/Anki-Android/issues/15278#issuecomment-2072142814