Function reducer

pub fn reducer<State, Action>(
    state: Substate<'_, Action, State, SnarkUserCommandVerifyState>,
    action: ActionWithMeta<&SnarkUserCommandVerifyAction>,
)
where
    State: SubstateAccess<SnarkUserCommandVerifyState> + SubstateAccess<SnarkState>,
    Action: From<SnarkUserCommandVerifyAction> + From<SnarkUserCommandVerifyEffectfulAction> + From<AnyAction> + EnablingCondition<State>,