半成品/成品入库：BOM 编号下拉按父件规格联动过滤（前后端双端改造）

- 后端 /inbound/{semi,product}/search-bom 增加 parent_spec 可选参数，Service 层在 MaterialBase.spec_model 上加等值过滤

inventory-backend/app/api/v1/inbound/product.py

@@ -60,7 +60,8 @@ def search_base():
 def search_bom():
     try:
         keyword = request.args.get('keyword', '')
-        data = ProductInboundService.search_bom_options(keyword)
+        parent_spec = request.args.get('parent_spec', None)
+        data = ProductInboundService.search_bom_options(keyword, parent_spec=parent_spec)
         return jsonify({"code": 200, "msg": "success", "data": data})
     except Exception as e:
         traceback.print_exc()