fix: reuse stream scanner buffer in channel handlers (#5225)

relay/channel/ollama/stream.go

@@ -1,7 +1,6 @@
 package ollama
 
 import (
-	"bufio"
 	"encoding/json"
 	"fmt"
 	"io"
@@ -70,7 +69,7 @@ func ollamaStreamHandler(c *gin.Context, info *relaycommon.RelayInfo, resp *http
 	defer service.CloseResponseBodyGracefully(resp)
 
 	helper.SetEventStreamHeaders(c)
-	scanner := bufio.NewScanner(resp.Body)
+	scanner := helper.NewStreamScanner(resp.Body)
 	usage := &dto.Usage{}
 	var model = info.UpstreamModelName
 	var responseId = common.GetUUID()