School Bus Market Size, Share & Industry Analysis, By Type (Type A, Type B, Type C, and Type D), By Propulsion (Diesel, Gasoline, CNG/LPG, Electric, and Hybrid), By Application (Public School, Private School, and Fleet Contractor), By Seating Capacity (Less than 30 Seats, 30–50 Seats, and Above 50 Seats), By Sales Channel (OEM and Retrofitted), and Regional Forecast, 2025-2032