Global Orexin Receptor Type 2 Market By Type (HTL-6641 , MK-8133 , Lemborexant , OPN-021 , and YNT-185), By Application (Insomnia , Narcolepsy , Sleep Disorders , and Major Depressive Disorder), By Region, and Key Companies - Industry Segment Outlook, Market Assessment, Competition Scenario, Trends and Forecast 2020-2029