chore(port-forward): support multiple port forwarded

internal/portforward/service/fs.go

@@ -3,13 +3,20 @@ package service
 import (
 	"fmt"
 	"os"
+	"strings"
 )
 
-func (s *Service) writePortForwardedFile(port uint16) (err error) {
+func (s *Service) writePortForwardedFile(ports []uint16) (err error) {
+	portStrings := make([]string, len(ports))
+	for i, port := range ports {
+		portStrings[i] = fmt.Sprint(int(port))
+	}
+	fileData := []byte(strings.Join(portStrings, "\n"))
+
 	filepath := s.settings.Filepath
 	s.logger.Info("writing port file " + filepath)
 	const perms = os.FileMode(0644)
-	err = os.WriteFile(filepath, []byte(fmt.Sprint(port)), perms)
+	err = os.WriteFile(filepath, fileData, perms)
 	if err != nil {
 		return fmt.Errorf("writing file: %w", err)
 	}