exclude unavailable items on apply(a) UI

[xotto]

most of weapons are no way to apply but they're on the catalog.

[PALU]

I agree it would be useful to get feedback on what you can and can't apply.

However, I'd rather have the unavailable items greyed out than removed, as removal may lead to confusion as to whether the items have gone missing. I would like to see the applicable items (i.e. those that can be applied) at the top of each section.