feat: 从黄果 NET hgdjnet-server 9bfbafe 导入 HKDJ 官网后端

来源：hgdjnet-server 9bfbafe10d417deea959bd53117bc88a10e60a83
项目身份 HKDJ / JHA-216，独立官网仓库，Jenkins 守卫键 hkdjnet
测试目录 /server/hkdj_net，App/Web API 30331/30332

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

app/middleware/validator/v9.go

@@ -0,0 +1,11 @@
+package validator
+
+import (
+	"github.com/gin-gonic/gin/binding"
+)
+
+// 替换gin 默认v8验证器
+// 改为v9
+func init() {
+	binding.Validator = new(defaultValidator)
+}