export function timeAgo(ts: number): string {
  const secs = Math.floor((Date.now() - ts) / 1000);
  if (secs < 5) return 'just now';
  if (secs < 60) return `${secs}s ago`;
  const mins = Math.floor(secs / 60);
  if (mins < 60) return `${mins}m ago`;
  const hrs = Math.floor(mins / 60);
  return `${hrs}h ago`;
}