SPRINGFIELD — In the midst of an historic budget standoff, legislative leaders and GOP Gov. Bruce Rauner could add to the oddity next week by hashing out their differences in public.Or maybe not.Details of a meeting between Rauner, top Democrats and Republicans are still murky after last month when they tentatively agreed to talk about the budget together in front of cameras.The request was made by a cadre of government reform groups, including the Illinois Campaign for Political Reform, which sought to broker an end …