/** getRandomValues remains available on HTTP, where randomUUID is unavailable. */
export function clockRequestId(source:{randomUUID?:()=>string;getRandomValues:(array:Uint8Array)=>Uint8Array}=globalThis.crypto) {
  if(source.randomUUID)return source.randomUUID();
  return Array.from(source.getRandomValues(new Uint8Array(16)),byte=>byte.toString(16).padStart(2,'0')).join('');
}