Vehicle to Grid (V2G) Market Size & Forecasts 2026-2035, By Segments (Charging Method, Vehicle Type, End User), Growth Opportunities, Innovation Landscape, Regulatory Shifts, Strategic Regional Insights (U.S., Japan, China, South Korea, UK, Germany, France), and Competitive Dynamics (Nuvve, Fermata Energy, Enel X, Virta, Nissan)