/** Client-generated IDs make explicit comment retries idempotent. */
export function isCommentId(value: unknown): value is string {
  return typeof value === "string" && /^[0-9a-f]{8}-[0-9a-f]{4}-4[0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$/i.test(value);
}