feat: promotional and purchase vouchers

src/BusProNet/Model/PromoVoucher.php

@@ -0,0 +1,37 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\BusProNet\Model;
+
+/**
+ * Promo voucher validation response from BPN API.
+ *
+ * Represents a validated promotional voucher (Aktionsgutschein) applied per participant.
+ * These vouchers provide discounts either as fixed amounts or percentages.
+ */
+final readonly class PromoVoucher
+{
+    public const APPLICABILITY_PER_PERSON = 'P';
+    public const APPLICABILITY_PER_BOOKING = 'B';
+
+    public function __construct(
+        public string $code,
+        public string $description,
+        public string $applicability,
+        public float $discountAmount,
+        public float $discountPercentage,
+        public float $minimumPrice,
+    ) {
+    }
+
+    public function isPerPerson(): bool
+    {
+        return self::APPLICABILITY_PER_PERSON === $this->applicability;
+    }
+
+    public function isPerBooking(): bool
+    {
+        return self::APPLICABILITY_PER_BOOKING === $this->applicability;
+    }
+}