Autonomous Train Market Size, Share & Industry Analysis, By Grade of Automation (GoA) (GoA1 (Manual Operation), GoA2 (Semi-Automated), GoA3 (Driverless), and Others), By Train Type (Metro/Urban Transit, High-Speed Rail, Freight Trains, and Others), By Component (Rolling Stock (Trains), Signaling & Train Control Systems, Communication Systems, Software & AI Systems, and Others), By Automation Technology (CBTC (Communication-Based Train Control), ETCS (European Train Control System), and Others), By Application (Passenger Transport and Freight Transport), and Regional Forecast, 2026–2034