ALL-1945 Item 2: Populate manufacturerSiteId from Honeywell locationId

Add manufacturerSiteId: coerceIdToString(location.locationID) to the object returned by mapThermostatDevice. HoneywellThermostat extends ThermostatDevice which already inherits manufacturerSiteId?: string from base Device — no interface change needed. Update mapThermostatDevice.test.ts to assert manufacturerSiteId equals locationId from same source. Branch: winston/all-1945-honeywell-manufacturer-site-id. PR title: feat(oem): set manufacturerSiteId on Honeywell thermostats (ALL-1945)