Every image a face is linked to — the search bar's face:<id> lookup (super-admin only).

A face box's own id (image_faces.id) exists on ONE image; what repeats across images is the person it is linked to. So faceId may be either: a box id resolves to that box's person, and anything else is taken as a person id. This is how a wrongly linked face is traced to every image that carries the same link, without touching the person's other faces.

A box with no person links nowhere else, so it returns just its own image. Scoped to the caller's current project(s) when given. Capped at 500: the grid loads an id list one image at a time.