Fixes T12538. Instead of hiding "closed" results unless only closed results match, show closed results but sort them to the bottom.
This fixes the actual issue in T12538, and I think this is probably the correct/best behavior for the global search.
It also makes all other typeaheads use this behavior. They currently have a "bug" where enabled user abcd makes it impossible to select disabled user abc. This manifests in some real cases, where enabled function members(abc) makes it impossible to disabled user abc in some function tokenizers.
If ths feels worse, we could go back to filtering in the simpler cases and introduce a rule like "show closed results if only closed results would be shown OR if query is an exact match for the disabled result", but that gets dicier because "exact match" is a fuzzy concept.
(There are a lot of other minor bad behaviors that this doesn't try to fix.)