Function audit_assignment_snapshot_authority 

pub async fn audit_assignment_snapshot_authority(
    store: &AssignmentSnapshotStore,
    controller: Option<&ClusterController>,
    snapshot: &AssignmentSnapshot,
) -> Result<(), String>

Audit a materialized assignment-drain outcome against the shared authority sequence. Ordinary assignments and still-draining transitions require no terminal decision.

Errors

Returns an error for missing/malformed authority history or a materialization that disagrees with the immutable terminal decision.