fix: Gateway 响应类型兼容 — 新增 FlexBool/FlexInt 处理设备返回的字符串类型字段

部分设备厂商（如华为）的 Gateway 响应中 bool/int 字段返回为字符串（wifi_enabled: "1"、battery_level: "30"），
导致 sonic 严格类型检查反序列化失败，整个设备实时数据丢失。

- 新增 FlexBool 类型：兼容 true/false、"1"/"0"、"true"/"false"
- 新增 FlexInt 类型：兼容 30、"30"、null
- SyncDeviceInfoResp 所有 bool/int 字段改用 Flex 类型
- 更新 B 端和 C 端 DTO 映射函数的类型转换

internal/service/asset/service.go

@@ -363,15 +363,15 @@ func (s *Service) fetchDeviceGatewayInfo(ctx context.Context, deviceID uint) *dt
 // 使用指针字段，未赋值的字段保持 nil（omitempty）
 func mapSyncRespToDeviceGatewayInfo(r *gateway.SyncDeviceInfoResp) *dto.DeviceGatewayInfo {
 	info := &dto.DeviceGatewayInfo{
-		OnlineStatus:    &r.OnlineStatus,
+		OnlineStatus:    flexIntPtr(r.OnlineStatus),
 		RunTime:         strPtr(r.RunTime),
 		ConnectTime:     strPtr(r.ConnectTime),
 		LastOnlineTime:  strPtr(r.LastOnlineTime),
 		LastUpdateTime:  strPtr(r.LastUpdateTime),
-		Rsrp:            &r.Rsrp,
-		Rsrq:            &r.Rsrq,
+		Rsrp:            flexIntPtr(r.Rsrp),
+		Rsrq:            flexIntPtr(r.Rsrq),
 		Rssi:            strPtr(r.RSSI),
-		Sinr:            &r.Sinr,
+		Sinr:            flexIntPtr(r.Sinr),
 		SSID:            strPtr(r.SSID),
 		WifiEnabled:     flexBoolPtr(r.WifiEnabled),
 		WifiPassword:    strPtr(r.WifiPassword),
@@ -382,21 +382,22 @@ func mapSyncRespToDeviceGatewayInfo(r *gateway.SyncDeviceInfoResp) *dto.DeviceGa
 		DailyUsage:      strPtr(r.DailyUsage),
 		DLStats:         strPtr(r.DLStats),
 		ULStats:         strPtr(r.ULStats),
-		LimitSpeed:      &r.LimitSpeed,
+		LimitSpeed:      flexIntPtr(r.LimitSpeed),
 		CurrentIccid:    strPtr(r.CurrentIccid),
-		MaxClients:      &r.MaxClients,
+		MaxClients:      flexIntPtr(r.MaxClients),
 		SoftwareVersion: strPtr(r.SoftwareVersion),
 		SwitchMode:      strPtr(r.SwitchMode),
-		SyncInterval:    &r.SyncInterval,
+		SyncInterval:    flexIntPtr(r.SyncInterval),
 		DeviceID:        strPtr(r.DeviceID),
 		DeviceName:      strPtr(r.DeviceName),
 		DeviceType:      strPtr(r.DeviceType),
 		IMEI:            strPtr(r.IMEI),
 		IMSI:            strPtr(r.IMSI),
-		Status:          &r.Status,
+		Status:          flexIntPtr(r.Status),
 	}
 	if r.BatteryLevel != nil {
-		info.BatteryLevel = r.BatteryLevel
+		n := int(*r.BatteryLevel)
+		info.BatteryLevel = &n
 	}
 	return info
 }
@@ -415,6 +416,11 @@ func flexBoolPtr(fb gateway.FlexBool) *bool {
 	return &b
 }
 
+func flexIntPtr(fi gateway.FlexInt) *int {
+	n := int(fi)
+	return &n
+}
+
 // Refresh 刷新资产数据（调网关同步）
 func (s *Service) Refresh(ctx context.Context, assetType string, id uint) (*dto.AssetRealtimeStatusResponse, error) {
 	switch assetType {
@@ -505,7 +511,7 @@ func (s *Service) updateDeviceFromSyncInfo(ctx context.Context, deviceID uint, r
 
 	// 更新设备 5 个存储字段
 	updates := map[string]any{
-		"online_status":        resp.OnlineStatus,
+		"online_status":        int(resp.OnlineStatus),
 		"software_version":     resp.SoftwareVersion,
 		"switch_mode":          resp.SwitchMode,
 		"last_gateway_sync_at": now,