支持delete，修改err输出为stderr

cmd/saastool/main.go

@@ -2,7 +2,6 @@ package main
 
 import (
 	"fmt"
-	"log/slog"
 	"os"
 )
 
@@ -10,11 +9,9 @@ func main() {
 	if err := Run(os.Args[1:]...); err != nil {
 		os.Exit(1)
 	}
-
 }
 
 func Run(args ...string) error {
-
 	name, args := ParseCommandName(args)
 
 	// 从参数中解析出命令
@@ -33,10 +30,9 @@ func Run(args ...string) error {
 		return RunVerify(args...)
 	case "task":
 		return RunTask(args...)
-
 	default:
-		err := fmt.Errorf(`unknown command "%s"`+"\n"+`Run 'saastool help' for usage`, name)
-		slog.Warn(err.Error())
+		err := fmt.Errorf(`unknown command "%v"`+"\n"+`Run 'saastool help' for usage`, name)
+		fmt.Fprintln(os.Stderr, err.Error())
 		return err
 	}
 }