feat: add xai channel

feat: add xai channel

feat: add xai channel

relay/constant/api_type.go

@@ -32,6 +32,7 @@ const (
 	APITypeBaiduV2
 	APITypeOpenRouter
 	APITypeXinference
+	APITypeXai
 	APITypeDummy // this one is only for count, do not add any channel after this
 )
 
@@ -92,6 +93,8 @@ func ChannelType2APIType(channelType int) (int, bool) {
 		apiType = APITypeOpenRouter
 	case common.ChannelTypeXinference:
 		apiType = APITypeXinference
+	case common.ChannelTypeXai:
+		apiType = APITypeXai
 	}
 	if apiType == -1 {
 		return APITypeOpenAI, false