Global Walk-in Refrigerators Market Size, Share & Demand Report By Product Type (Walk-in Coolers, Walk-in Freezers, Combination Units), By Installation Type (Indoor, Outdoor, Modular), By Panel Construction (PUF, PIR, EPS), By Temperature Range (Medium, Low, Ultra-Low), By Capacity (Small, Medium, Large), By End-Use Industry (Foodservice, Retail, Pharmaceutical, Logistics), By Region & Segment Forecasts, 2025–2030