User settable device class (temperature, humidity etc.) for each area

This would require frontend and backend changes, but the idea is to be able to set default sensors etc. for each device class.

A very terrible mock up:

The future use of this would be in conversation responses and templates etc. to get the temperature, humidity, etc. of an area as using the climate platform is OK, but isnt accurate if you have radiator thermostats about 5°C below the actual temperature or a thermostat that rounds the temperature

An easier way to solve this is to just use custom sentences.