fix(client): keep the daemon alive after logout on linux

backend/internal/client/install.go

@@ -132,6 +132,7 @@ func startService(home, binary, logFile string) error {
 	if err := writeFile(unitPath(home), []byte(systemdService(binary)), 0o644); err != nil {
 		return err
 	}
+	_ = command("loginctl", "enable-linger")
 	if err := command("systemctl", "--user", "daemon-reload"); err != nil {
 		return err
 	}