ROCHESTER — The state’s largest homebuilder is asking the Rochester City Council for approval of a plat for creating 108 homes on 56 acres in the city’s northwest quadrant. Lennar Homes plans to continue work started by Rochester-based DeWitz Home Builders in the existing Pebble Creek development, and the latest request is proposed as one step in a larger development project. On Monday, the City Council will be asked to approve a final plat for …