fix: allow to re-use a deleted ref in articles

database/migrations/shop/2025_10_15_120000_update_shop_articles_ref_unique_index.php

@@ -0,0 +1,30 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    /**
+     * Run the migrations.
+     */
+    public function up(): void
+    {
+        Schema::table('shop_articles', function (Blueprint $table) {
+            $table->dropUnique('ref');
+            $table->unique(['ref', 'deleted_at'], 'shop_articles_ref_deleted_at_unique');
+        });
+    }
+
+    /**
+     * Reverse the migrations.
+     */
+    public function down(): void
+    {
+        Schema::table('shop_articles', function (Blueprint $table) {
+            $table->dropUnique('shop_articles_ref_deleted_at_unique');
+            $table->unique('ref');
+        });
+    }
+};