Global Fermentation-Based Natural Vanillin Market Size, Share & Demand Report By Production Source (Ferulic Acid-Based Fermentation, Eugenol-Based Fermentation, Glucose/Sugar-Based Bioconversion, Lignin-Derived Biovanillin), By Form (Powder/Crystalline, Liquid, Encapsulated/Granular), By Application (Food & Beverages, Fragrances & Personal Care, Pharmaceuticals & Nutraceuticals, Animal Nutrition, Industrial Applications), By Distribution Channel (Direct B2B Sales, Ingredient Distributors, E-commerce Platforms), By Region & Segment Forecasts, 2026–2031