CHICAGO — Former Illinois House Speaker Michael Madigan, for decades the most powerful politician in the state, was indicted Wednesday on federal racketeering charges alleging his elected office and political operation were a criminal enterprise that provided personal financial rewards for him and his associates. The 22-count indictment returned by a federal grand jury comes after a yearslong federal investigation and alleges Madigan participated in an array of bribery and extortion schemes from 2011 to 2019 aimed at using the power of his office for personal gain. The long-awaited charges pun…