Global Caffeine Market Size, Share & Demand Report By Product Type (Natural Caffeine, Synthetic Caffeine), By Source (Coffee Beans, Tea Leaves, Guarana, Cocoa Beans, Synthetic Sources), By Application (Beverages, Pharmaceuticals, Food & Confectionery, Dietary Supplements, Cosmetics & Personal Care), By Form (Powder, Liquid), By Distribution Channel (B2B Industrial Supply, Direct Manufacturer Contracts, Specialty Ingredient Suppliers, Online Ingredient Platforms) By Region & Segment Forecasts, 2026–2031