onFocusBadge is currently a boolean or a custom badge. For Kibaba, where we have multiple item types, we need a custom badge per item.

Would be good if onFocusBadge supported passing in a callback which could run on each option to create a custom badge. Alternatively, maybe onFocusBadge needs to be moved into the rendered option itself and not be something managed by EuiSelectable? Rather, an option gets a isFocused flag passed into it?

Multiple ways to accomplish this probably.