SPRINGFIELD — Gov. J.B. Pritzker on Wednesday signed a law providing full disability benefits to Chicago police officers and firefighters struck by COVID-19 before vaccines were available, presiding over an emotional statehouse ceremony that marked the end of a financial struggle for responders including the brother of Comptroller Susana Mendoza.The Act-of-Duty law, HB3162, ensures disability benefits of 75% of salary plus health insurance for anyone unable to work after contracting the coronavirus from March 9, 2020 …