Indicate that a matching preset is a hidden (non-searchable) one

There even exist some mapping mistakes which could be alleviated by not offering a preset for certain search keywords in the preset bar, and instead showing a hint message instead. For example (see https://github.com/openstreetmap/id-tagging-schema/issues/354), courtyard matches a preset but most often a courtyard should be mapped as a whole in a building polygon instead. I'm sure there exist more non-features which could be relatively easily catched at that stage as well (pokemon go gyms could be an example).

Somehow related: Currently, iD tries very hard to offer a preset for basically any search term: For example, until recently, the presets didn't include a term for a spillway, but the search still resulted in some unrelated results (see screenshot):

While this is not harmful in most cases, it would be even better to include a generic hint here which could explain that the tagging presets in iD are not exhaustive and perhaps indicate the users to consider the OSM wiki to find the correct tagging.