A 28-year-old woman is reviewed 16 weeks after surgical fixation of a comminuted fracture of the distal femur with open reduction and internal plate fixation. Radiographs show complete bridging of the fracture site with dense callus, obliteration of the fracture line, and early resorption of excess callus. The patient is able to bear full weight without pain and has regained near-normal knee range of motion. Which stage of fracture healing is now predominant, and what is the expected outcome at this timepoint?