feat(auth): 添加设备绑定数量限制检查

在设备绑定逻辑中添加对设备绑定数量的限制检查，当超过限制时返回特定错误码
同时在用户注册、登录等流程中处理设备绑定数量超限的错误情况

internal/logic/auth/userRegisterLogic.go

@@ -127,17 +127,20 @@ func (l *UserRegisterLogic) UserRegister(req *types.UserRegisterRequest) (resp *
 		return nil
 	})
 	// Bind device to user if identifier is provided
-	if req.Identifier != "" {
-		bindLogic := NewBindDeviceLogic(l.ctx, l.svcCtx)
-		if err := bindLogic.BindDeviceToUser(req.Identifier, req.IP, req.UserAgent, userInfo.Id); err != nil {
-			l.Errorw("failed to bind device to user",
-				logger.Field("user_id", userInfo.Id),
-				logger.Field("identifier", req.Identifier),
-				logger.Field("error", err.Error()),
-			)
-			// Don't fail register if device binding fails, just log the error
-		}
-	}
+    if req.Identifier != "" {
+        bindLogic := NewBindDeviceLogic(l.ctx, l.svcCtx)
+        if err := bindLogic.BindDeviceToUser(req.Identifier, req.IP, req.UserAgent, userInfo.Id); err != nil {
+            var ce *xerr.CodeError
+            if errors.As(err, &ce) && ce.GetErrCode() == xerr.DeviceBindLimitExceeded {
+                return nil, ce
+            }
+            l.Errorw("failed to bind device to user",
+                logger.Field("user_id", userInfo.Id),
+                logger.Field("identifier", req.Identifier),
+                logger.Field("error", err.Error()),
+            )
+        }
+    }
 	if l.ctx.Value(constant.LoginType) != nil {
 		req.LoginType = l.ctx.Value(constant.LoginType).(string)
 	}