Variable createCheckoutSchema`Const`

createCheckoutSchema: ZodObject<
    {
        amount: ZodCoercedNumber<unknown>;
        currency: ZodString;
        description: ZodOptional<ZodString>;
        metadata: ZodOptional<ZodRecord<ZodString, ZodString>>;
    },
    $strict,
> = ...

创建 checkout（支付意图）入参（旧 CreateCheckoutDto）。