Constrain Accepted Reference Identifiers In Forced Reconciliation Request

Currently, there is no validation performed on the Reference Identifier provided in a Forced Reconciliation Request. It's not clear this is the correct behavior.

1. System of Record API Users should not be able to select a Reference ID (other than new) that does not match a potential match candidate. Only Reconciliation Managers or Matchgrid Administrators should be able to do so.
2. Even in such a scenario, it should not be possible to force the selection of a Reference ID that has not yet been assigned, in order to avoid conflicts with the Reference ID generation algorithms (and in particular Sequence). An exception to this might be bulk initial load (CO-1678).
3. If the record is already matched, Forced Reconciliation Requests should be denied, except maybe by a Matchgrid Administrator. (It's really a Join/Split at that point.)