General
Configure:
- Name: the administrative label and, for fixed-code coupons, the customer code.
- Promotion type: campaign or coupon.
- Discount type: percentage of the service base price or fixed amount.
- Discount value: a non-negative value valid for the selected type.
- Promotion period: the dates during which the promotion may be applied.
The promotion period and appointment-time restrictions are separate checks.
