feat: voucher purchase flow

src/BusProNet/Model/VoucherTemplate.php

@@ -0,0 +1,21 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\BusProNet\Model;
+
+/**
+ * A voucher design offered for online sale (GUTSCHEINVORLAGEN).
+ *
+ * The id doubles as the key for the local thumbnail, see VoucherThumbnailResolver.
+ */
+final readonly class VoucherTemplate
+{
+    public function __construct(
+        public int $id,
+        public string $type,
+        public string $label,
+        public ?string $note = null,
+    ) {
+    }
+}