Cops are looking to question the former handyman lover of slain Queens mom Orsolya Gaal who had intimate knowledge of her home — including where the family kept a spare key, The Post has learned. The man, who has not yet been formally identified as a person of interest or suspect in the gruesome slaying, is believed to have had a romantic relationship with the 51-year-old married mother of two before the affair went south, law-enforcement sources said. It’s unclear when the relationship began and ended, but according to sources familiar with the case, the man knew where the family...