Exclude detail pages in pages modal when editing a standard page

@Angel Dagondon When in my webapp_1 detail page, if I look at the modal, both this detail page and my blog one appear, but

a) both appear as disabled, when I think they are not. (it’s probably a different setting which determines whether a detail page is enabled/ disabled)

b) It would be nice to put something in the list to say whether they are detail pages, e.g. the URL could say /gallery/<item-slug>