Strukturierte Datenvalidierung mit ArrayBuffer und DataView für binäre Route Handler

export function parseBinaryHeaderPayload(buffer) {
  if (!(buffer instanceof ArrayBuffer) || buffer.byteLength < 8) {
    throw new TypeError('Invalid buffer length or type');
  }
  const view = new DataView(buffer);
  const magic = view.getUint32(0, false);
  const payloadSize = view.getUint32(4, false);
  if (magic !== 0x4E455854) {
    throw new RangeError('Invalid magic byte signature');
  }
  return { magic, payloadSize };
}