export async function measureFlow(operation, record, clock = performance) {
  let start;
  try {
    start = clock.now();
  } catch {
    // A missing timer must not prevent the operation.
  }
  let outcome = "error";
  try {
    const result = await operation();
    outcome = "ok";
    return result;
  } finally {
    try {
      const durationMs = clock.now() - start;
      if (Number.isFinite(durationMs) && durationMs >= 0) {
        // Do not wait for telemetry delivery; handle rejected collectors.
        Promise.resolve(record({ durationMs, outcome })).catch(() => {});
      }
    } catch {
      // Timer and collector failures must not replace the result or error.
    }
  }
}