feat: restructure checkout steps, add Kauf/Abo selection and product display flags

shop/lib/license-transform.ts

@@ -84,7 +84,8 @@ export function buildCustomerSnapshot(
 export function buildOrderSnapshot(
   selections: WizardSelections,
   products: Product[],
-  categories: Category[]
+  categories: Category[],
+  billingInterval?: 'one_time' | 'monthly'
 ): OrderSnapshot {
   const items: OrderItem[] = []
   let subtotal = 0
@@ -127,10 +128,10 @@ export function buildOrderSnapshot(
   const taxAmount = Math.round(subtotal * (dominantTaxRate / 100) * 100) / 100
   const total = Math.round((subtotal + taxAmount) * 100) / 100
 
-  // Wenn alle Items one_time sind → billing_cycle = 'one_time', sonst 'monthly'
-  const billingCycle = items.every((i) => i.billing_interval === 'one_time')
+  // Wenn billingInterval übergeben, dieses nutzen; sonst automatisch ermitteln
+  const billingCycle = billingInterval || (items.every((i) => i.billing_interval === 'one_time')
     ? 'one_time'
-    : 'monthly'
+    : 'monthly')
 
   return {
     schema_version: 1,