Global Hair Fiber Market Size, Share & Demand Report By Product Type (Natural Hair Fibers (Keratin, Cotton-Based), Synthetic Hair Fibers (Rayon, Nylon), Hybrid Fiber Blends), By Application (Scalp Hair Thinning, Beard & Mustache Enhancement, Eyebrow Enhancement), By Distribution Channel (Online Retail, Pharmacies & Drug Stores, Specialty Stores, Supermarkets & Hypermarkets, Professional Distribution), By End User (Individual Consumers, Professional Salons & Clinics), By Gender (Male, Female), By Region & Segment Forecasts, 2026–2031