SPRINGFIELD — An Illinois case on sex-offender rights in the internet age may have been bolstered by a decision from the nation’s top court this week.The U.S. Supreme Court’s striking Monday of a social media ban for North Carolina offenders amounted to a recognition of the ubiquity of social media and a defense of First Amendment principles as they pertain to the web.And although the Illinois law at issue only requires offenders to disclose social media activity, rather than prohibiting it outright, the …