Return the IDs of shares on file that are NOT present in the
provided attendee list. These are the "out-of-room" entries that a
room-scoped share UI cannot manage and must preserve. IDs are
returned in their original form (file.shared[] may already be
cleaned by the cloud; we don't transform). Comparison is done in
normalized form so raw and cleaned ids on either side still match.
Return the IDs of shares on
filethat are NOT present in the provided attendee list. These are the "out-of-room" entries that a room-scoped share UI cannot manage and must preserve. IDs are returned in their original form (file.shared[]may already be cleaned by the cloud; we don't transform). Comparison is done in normalized form so raw and cleaned ids on either side still match.