export function decodeJwtSubject(token: string): {user_id: string; id: string; role: number} | null {
  try {
    const payloadB64 = token.split('.')[1];
    const payload = JSON.parse(atob(payloadB64.replace(/-/g, '+').replace(/_/g, '/')));
    return JSON.parse(payload.sub);
  } catch {
    return null;
  }
}