Prevent user-disabled objects from appearing

Unchecking individual QSObjects in the catalog would prevent them from appearing when you searched in the first pane, but they would still appear in the third pane and when right arrowing. I’ve fixed that.

Ideally, we could take care of this as part of #1601, but I gather @tiennou is too busy right now to take on additional features. I’ve at least tried to do something that won’t conflict.