feat: add backend_v1 migration

backend_v1/app/errorx/middleware.go

@@ -0,0 +1,38 @@
+package errorx
+
+import "github.com/gofiber/fiber/v3"
+
+// 全局实例
+var DefaultSender = NewResponseSender()
+
+// Middleware 错误处理中间件
+func Middleware(c fiber.Ctx) error {
+	err := c.Next()
+	if err != nil {
+		return DefaultSender.SendError(c, err)
+	}
+	return nil
+}
+
+// 便捷函数
+func Wrap(err error) *AppError {
+	if err == nil {
+		return nil
+	}
+
+	if appErr, ok := err.(*AppError); ok {
+		return &AppError{
+			Code:        appErr.Code,
+			Message:     appErr.Message,
+			StatusCode:  appErr.StatusCode,
+			Data:        appErr.Data,
+			originalErr: appErr,
+		}
+	}
+
+	return DefaultSender.handler.Handle(err)
+}
+
+func SendError(ctx fiber.Ctx, err error) error {
+	return DefaultSender.SendError(ctx, err)
+}