generateTraceId function
Generates a 16-character hex trace ID from the current timestamp and a random component.
Not cryptographically secure — suitable for log correlation only.
Implementation
String generateTraceId() {
const timestampMask = 0xffffffff;
const randomBound = 0x7fffffff;
const hexPadLen = 8;
final now = DateTime.now().microsecondsSinceEpoch;
final r = _random.nextInt(randomBound);
return (now & timestampMask).toRadixString(16).padLeft(hexPadLen, '0') +
r.toRadixString(16).padLeft(hexPadLen, '0');
}