Global Thermal Wellness Market Size, Share, Demand Report By Service Type (Thermal Spas, Hot Springs Resorts, Balneotherapy Centers, Wellness Retreats with Hydrotherapy, Medical & Therapeutic Clinics), By Application (Health Rehabilitation, Relaxation & Stress Relief, Skin Treatment, Detox & Weight Management), By End User (Individuals, Tourists, Corporates, Medical Travelers), By Region & Segment Forecasts, 2025–2030