Self-testing Market Size & Forecasts 2026-2035, By Segments (Product Type, Sample Type, Usage, Application, Test Type, Distribution Channel), Growth Opportunities, Innovation Landscape, Regulatory Shifts, Strategic Regional Insights (U.S., Japan, China, South Korea, UK, Germany, France), and Competitive Dynamics (Roche, Abbott, Siemens Healthineers, Becton Dickinson, QuidelOrtho)