feat(03.1-01): 建立设备实时 Gateway 调用链路，替换 mock 数据

- GetRealtimeStatus() device case 新增 Gateway sync-info 实时调用（IMEI/SN 优先，gatewayClient nil 安全）
- 新增 mapSyncRespToDeviceGatewayInfo() 将 SyncDeviceInfoResp 映射为 B 端 DeviceGatewayInfo DTO
- 新增 strPtr() 辅助函数（空字符串→nil，防止 JSON 出现大量空字符串字段）
- client_asset.go 删除 buildMockDeviceRealtime()，改为调用 assetService.GetRealtimeStatus() 获取真实数据
- 新增 mapDeviceGatewayInfoToClientInfo() 将 B 端 DeviceGatewayInfo 映射为 C 端 DeviceRealtimeInfo
- Gateway 调用失败时 DeviceRealtime 返回 null，不阻断主流程

internal/handler/app/client_asset.go

@@ -185,9 +185,15 @@ func (h *ClientAssetHandler) GetAssetInfo(c *fiber.Ctx) error {
 		BoundDeviceName:     resolved.Asset.BoundDeviceName,
 	}
 
-	// TODO: Gateway 同步接口对接后，替换为真实设备实时数据
+	// 调用服务层获取设备实时 Gateway 数据（per D-11）
+	// Gateway 失败时 DeviceRealtime 为 null，不阻断主流程（per D-06）
 	if resp.AssetType == "device" {
-		resp.DeviceRealtime = buildMockDeviceRealtime()
+		realtimeResp, realtimeErr := h.assetService.GetRealtimeStatus(
+			c.UserContext(), "device", resp.AssetID,
+		)
+		if realtimeErr == nil && realtimeResp.DeviceRealtime != nil {
+			resp.DeviceRealtime = mapDeviceGatewayInfoToClientInfo(realtimeResp.DeviceRealtime)
+		}
 	}
 
 	return response.Success(c, resp)
@@ -592,44 +598,76 @@ func packageStatusName(status int) string {
 	}
 }
 
-// buildMockDeviceRealtime 构建设备实时状态假数据
-// TODO: Gateway 同步接口对接后移除此函数，改为调用 Gateway 接口获取真实数据
-func buildMockDeviceRealtime() *dto.DeviceRealtimeInfo {
-	onlineStatus := int64(1)
-	batteryLevel := int64(85)
-	deviceStatus := int64(1)
-	runTime := "3600"
-	connectTime := "3500"
-	rsrp := int64(-80)
-	rsrq := int64(-10)
-	rssi := "-65"
-	sinr := int64(15)
-	ssid := "JunHong-WiFi"
-	wifiEnabled := true
-	wifiPassword := "12345678"
-	ipAddress := "192.168.1.1"
-	lanIP := "192.168.1.1"
-	dailyUsage := "0"
-	maxClients := int64(32)
-	switchMode := 0
-
-	return &dto.DeviceRealtimeInfo{
-		OnlineStatus: &onlineStatus,
-		BatteryLevel: &batteryLevel,
-		Status:       &deviceStatus,
-		RunTime:      &runTime,
-		ConnectTime:  &connectTime,
-		Rsrp:         &rsrp,
-		Rsrq:         &rsrq,
-		Rssi:         &rssi,
-		Sinr:         &sinr,
-		SSID:         &ssid,
-		WifiEnabled:  &wifiEnabled,
-		WifiPassword: &wifiPassword,
-		IPAddress:    &ipAddress,
-		LANIP:        &lanIP,
-		DailyUsage:   &dailyUsage,
-		MaxClients:   &maxClients,
-		SwitchMode:   &switchMode,
+// mapDeviceGatewayInfoToClientInfo 将 B 端 DeviceGatewayInfo 映射为 C 端 DeviceRealtimeInfo
+// B 端和 C 端结构独立，通过映射函数转换（per D-08）
+func mapDeviceGatewayInfoToClientInfo(g *dto.DeviceGatewayInfo) *dto.DeviceRealtimeInfo {
+	if g == nil {
+		return nil
 	}
+	info := &dto.DeviceRealtimeInfo{}
+	if g.OnlineStatus != nil {
+		v := int64(*g.OnlineStatus)
+		info.OnlineStatus = &v
+	}
+	if g.BatteryLevel != nil {
+		v := int64(*g.BatteryLevel)
+		info.BatteryLevel = &v
+	}
+	if g.Status != nil {
+		v := int64(*g.Status)
+		info.Status = &v
+	}
+	info.RunTime = g.RunTime
+	info.ConnectTime = g.ConnectTime
+	info.LastOnlineTime = g.LastOnlineTime
+	info.LastUpdateTime = g.LastUpdateTime
+	if g.Rsrp != nil {
+		v := int64(*g.Rsrp)
+		info.Rsrp = &v
+	}
+	if g.Rsrq != nil {
+		v := int64(*g.Rsrq)
+		info.Rsrq = &v
+	}
+	info.Rssi = g.Rssi
+	if g.Sinr != nil {
+		v := int64(*g.Sinr)
+		info.Sinr = &v
+	}
+	info.SSID = g.SSID
+	info.WifiEnabled = g.WifiEnabled
+	info.WifiPassword = g.WifiPassword
+	info.IPAddress = g.IPAddress
+	info.WANIP = g.WANIP
+	info.LANIP = g.LANIP
+	info.MACAddress = g.MACAddress
+	info.DailyUsage = g.DailyUsage
+	info.DLStats = g.DLStats
+	info.ULStats = g.ULStats
+	if g.LimitSpeed != nil {
+		v := int64(*g.LimitSpeed)
+		info.LimitSpeed = &v
+	}
+	info.CurrentIccid = g.CurrentIccid
+	if g.MaxClients != nil {
+		v := int64(*g.MaxClients)
+		info.MaxClients = &v
+	}
+	info.SoftwareVersion = g.SoftwareVersion
+	if g.SwitchMode != nil {
+		// SwitchMode 在 B 端为字符串（"0"/"1"），C 端为整型（0/1），需解析转换
+		if n, convErr := strconv.Atoi(*g.SwitchMode); convErr == nil {
+			info.SwitchMode = &n
+		}
+	}
+	if g.SyncInterval != nil {
+		v := int64(*g.SyncInterval)
+		info.SyncInterval = &v
+	}
+	info.DeviceID = g.DeviceID
+	info.DeviceName = g.DeviceName
+	info.DeviceType = g.DeviceType
+	info.Imei = g.IMEI
+	info.Imsi = g.IMSI
+	return info
 }