PERK Inhibitors Market by Product / Offering Type, Development / Market Maturity Stage, Application Area (Solid-Tumor Oncology, Hematologic Oncology, Respiratory Fibrosis Research, Metabolic and Endocrine Disease Research, Neurodegenerative and Cognitive-Disease Research and General ER-Stress / Unfolded-Protein-Response Biology), Mechanistic Positioning, End User / Buyer Type, Research Format / Assay Modality, Geographical Regions, and Leading Players – Trends and Forecasts, 2026-2040