EXCLUSIVE TO YOU IN YOUR CITY   HER FAVOURITE DOLL -- Stuart Damon, as a cautious Nemesis agent, questions Adrienne Corri, who plays a lady addicted to practice of witchcraft, about her unusual “toy” in “The Night People” episode of “The Champions,” to be colorcast on the NBC Television Network Monday, August 12 (8-9 p.m. NYT).   (A)   NBC-TV CAPTION SUBJECTS:     Stuart Damon and Adrienne Corri PROGRAM:     “The Night People” episode colorcast on “The Champions” TIME:     NBC Television Network, Monday, August 12 (8-9 p.m. NYT)