Function add_member_task 

pub async fn add_member_task(
    adding: AddingMember,
    read: Read,
    clock: Clock,
) -> Result<MemberAdded>

For an app’s tasks: Tasks::new().task("sofie_identity.add_member", add_member_task), then <app> task sofie_identity.add_member --email … --area … [--role …].