Chess legend Judit Polgar on Monday turned down Hungarian Prime Minister Peter Magyar’s offer to join his push to break with the Viktor Orban era as the country’s president.The pro-European conservative had nominated Polgar, widely considered the greatest woman to have taken to the chequered board, as a figure from outside politics to help carry out his promise of “regime change” from Orban’s hardline 16-year tenure.“I do not feel I have the strength to take on the historic responsibility of...