publish method
Implementation
Future<void> publish(final AgentLinkAnnouncement announcement) async {
await root.create(recursive: true);
final file = fileFor(announcement.protocolScheme);
final temporary = File('${file.path}.tmp');
await temporary.writeAsString(
'${jsonEncode(announcement.toJson())}\n',
flush: true,
);
await temporary.rename(file.path);
}