A 28-year-old male motorcyclist is hit by a truck and sustains a compound fracture of the right femur. At the scene, there is a 2 cm laceration over the fracture site with minimal visible contamination. The patient is brought to the hospital within 90 minutes. On examination, the limb is neurovascularly intact, and there is no evidence of compartment syndrome. Radiographs confirm a simple transverse femoral shaft fracture. What is the Gustilo classification, and what is the recommended antibiotic regimen?