feat(inbound): handle batch duplication gracefully, support spec search, and auto-fill historical locations

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

@@ -218,7 +218,13 @@ def submit():
         if not location:
             return jsonify({"code": 400, "msg": "入库失败：库位为必填项，不能为空！"}), 400
 
-        new_stock = BuyInboundService.handle_inbound(data)
+        result = BuyInboundService.handle_inbound(data)
+
+        # 检查是否返回了业务校验错误
+        if isinstance(result, dict) and result.get('error'):
+            return jsonify({"code": 400, "msg": result['error']}), 400
+
+        new_stock = result
 
         return jsonify({
             "code": 200,