A pair of Dorchester teens scheduled for trial next week on charges that included first-degree murder yesterday pleaded guilty to manslaughter for  the shooting death of Leudis Mejia Sanchez outside his son's apartment on Trent Street in Dorchester on Aug. 12, 2024, the Suffolk County District Attorney's office reports. In exchange for their plea, which also included admitting shooting, but not killing, Mejia Sanchez's son, and home invasion, Suffolk Superior Court Judge Mary Ames sentenced Manuel Guerrero, 19, and Luis Perez, 18, to 18 to 24 years in state prison. The DA's office provided this account: On August 12, 2024, Guerrero and Perez were seen on surveillance video exiting the rear passenger door of a Kia Forte at the intersection of Trent and Clarkson streets. They were seen walking up to the third floor of 5 Trent Street and knocking on the door. Leudis Concepcion, 20, opened the door, saw the two masked men with guns, and quickly closed the door.…