Global Allergy Immunotherapy Market By Treatment Type (Subcutaneous Immunotherapy (SCIT) and Sublingual Immunotherapy (SLIT)), By Type (Tablets and Drops), By Allergy Type (Allergic Rhinitis, Allergic Asthma, and Others), By Distribution Channel (Hospital Pharmacy, Online Pharmacy, and Retail Pharmacy), Region and Companies – Industry Segment Outlook, Market Assessment, Competition Scenario, Trends and Forecast 2025-2034