def evaluate_case(case):
    """Evaluate one synthetic manual-handoff provenance fixture.

    Return these fields:
    package_state, outbound_identity_state, change_note_state, derivation_state,
    external_source_state, reviewer_state, provenance_gap, decision, reason.
    """
    raise NotImplementedError("implement the CON-021 provenance round-trip evaluator")