feat: 开放API产品相关

app/openapi/model/ProductRelatedModel.php

@@ -0,0 +1,19 @@
+<?php
+declare (strict_types = 1);
+
+namespace app\openapi\model;
+
+use app\common\model\ProductRelatedBaseModel;
+
+/**
+ * 产品 - 相关产品模型
+ * @mixin \think\Model
+ */
+class ProductRelatedModel extends ProductRelatedBaseModel
+{
+    // 关联产品
+    public function product()
+    {
+        return $this->belongsTo(ProductModel::class, 'related_product_id', 'id');
+    }
+}