Allergic Rhinitis Treatment Market Size, Share & Industry Analysis, By Drug Class (Corticosteroids, H1 Antihistamines, Leukotriene Receptor Antagonists, Decongestants, Mast Cell Stabilizers, Anticholinergics, and Allergen Immunotherapy Products), By Disease (Seasonal Allergic Rhinitis and Perennial Allergic Rhinitis), By Age Group (Pediatric and Adults), By Type (Prescription and OTC), By Route of Administration (Intranasal, Oral, Sublingual, and Subcutaneous), By Distribution Channel (Hospital Pharmacies, Retail Pharmacies, and Specialty Pharmacies), and Regional Forecast, 2026-2034