refactor: ensure proper UTF-8 character boundaries when truncating sc…

…ript output

alert/sender/plugin.go

@@ -6,6 +6,7 @@ import (
 	"os"
 	"os/exec"
 	"time"
+	"unicode/utf8"
 
 	"github.com/ccfos/nightingale/v6/alert/astats"
 	"github.com/ccfos/nightingale/v6/models"
@@ -87,10 +88,20 @@ func alertingCallScript(ctx *ctx.Context, stdinBytes []byte, notifyScript models
 	err, isTimeout := sys.WrapTimeout(cmd, time.Duration(config.Timeout)*time.Second)
 
 	res := buf.String()
-	
+
 	// 截断超出长度的输出
 	if len(res) > 512 {
-		res = res[:512] + "..."
+		// 确保在有效的UTF-8字符边界处截断
+		validLen := 0
+		for i := 0; i < 512 && i < len(res); {
+			_, size := utf8.DecodeRuneInString(res[i:])
+			if i+size > 512 {
+				break
+			}
+			i += size
+			validLen = i
+		}
+		res = res[:validLen] + "..."
 	}
 
 	NotifyRecord(ctx, []*models.AlertCurEvent{event}, channel, cmd.String(), res, buildErr(err, isTimeout))