3rd Rail Current Collector Market Size & Forecasts 2026-2035, By Segments (Sales Channel, Collector, End User, Material, Rail Contact Position, Speed, Application), Growth Opportunities, Innovation Landscape, Regulatory Shifts, Strategic Regional Insights (U.S., Japan, China, South Korea, UK, Germany, France), and Competitive Dynamics (Stadler Rail, CRRC, Alstom, Siemens, Kawasaki Heavy)