The Big Apple judge who cut loose an alleged nut accused of randomly attacking a subway cello player is a former Legal Aid attorney with ties to progressive politicians. Judge Marva Brown, who opted Thursday to release the 23-year-old alleged attacker — who has at least eight prior arrests — was only recently elected to her judicial role after nearly two decades as a public defender. Brown became a Brooklyn civil court judge in November after campaigning as self-described “zealous advocate, compassionate advisor, respected negotiator and skilled litigator,” according to her campaign site. The married mom of three was endorsed...