A handful of Cook County prosecutors will be stationed in certain Chicago police districts as part of a new effort by State’s Attorney Kimberly M. Foxx to stem the tide of gun violence in the city.Foxx announced the office’s new Gun Crimes Strategy Unit during a speech Wednesday before the City Club of Chicago where she recounted the policy decisions she’s made since she took office Dec. 1.“This is not a unit that is simply waiting in the wings for something to happen,” Foxx told reporters …