NEW YORK — The Nets are one of a number of playoff and championship contenders with tangible interest in veteran free agent forward P.J. Tucker, multiple sources told the New York Daily News. Tucker became an unrestricted free agent after declining his $7 million player option with the Miami Heat earlier this week. He is great friends — “brothers,” in his words — with Nets star Kevin Durant, and adding a player of Tucker’s ilk would provide a much-needed toughness and frontcourt floor spacing to a Nets team lacking both. Tucker, however, would likely have to take a pay cut to join the Nets. Br…