EDITOR'S NOTE - The kibitzers this night include a playwright from Spain, a drug dealer, a Queens housewife, a master chess player from Harlem, a biker and assorted yuppies. They are in a hotel next door to the old theater where Garry Kasparov and Anatoly Karpov sit hunched over their chessboard. They watch the action on closed-circuit TV and debate the players' every move, their politics, their diet, their very nose scratchings.