macForWorker function
Deterministic, locally-administered unicast MAC unique per worker. worker-mac-1 -> da:d7:a6:2d:e9:c6 (the original base MAC), -2 -> ...c7, etc.
Implementation
String macForWorker(String workerId) {
final match = RegExp(r'(\d+)$').firstMatch(workerId);
final n = match != null ? int.parse(match.group(1)!) : 1;
final lastOctet = (0xc6 + n - 1) & 0xff;
final hex = lastOctet.toRadixString(16).padLeft(2, '0');
return 'da:d7:a6:2d:e9:$hex';
}