A federal judge has declined to throw out a claim that a Freeborn & Peters LLP partner bungled his representation of a client involved in a business dispute. In a written opinion, U.S. District Judge Gary Feinerman did not rule on the merits of the allegation that legal malpractice on the part of Neal H. Levin left North Carolina businessman Jeffrey P. Eckert owing $1 million to another Levin client. But Feinerman rejected the argument that the malpractice claim is barred by res judicata. Eckert could not …