A Vermont construction company and the developers of the stalled “Midtown” project in Portland have settled a lawsuit over the troubled mixed-use project. PC Constuction filed a lawsuit in federal court a month ago, saying that The Federated Cos., developers of the Bayside project, set up its corporate structure to allow it to walk away from the project without paying some of its contractors. Those contractors included PC Construction, which said it was owed $235,000 by the developer.