Residential Boiler Market Size, Share, and Industry Analysis By Capacity (Less than 30 kW, 30-60 kW, and Above 60 kW), By Fuel Type (Oil -fired boilers, Gas-fired boilers, Electric Boilers, and Others (Wood Boilers)), By Installation Type (Floor Standing and Wall Mounted), By End User (Single Family, Multi-Family, Apartments, and Others (Townhouses)), and Regional Forecast, 2026-2034