feat: provides power level and power percent

[swingerman]

Fixes #196

[sonarqubecloud]

Quality Gate passed

Issues
3 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud

[Bergoglio]

Ok, first problem :
hvac_power_percent from states returnes a value with decimals but it is not necessary by my point of view (instead of 33,57 it is sufficient 34, intead of 33,50 > 33); decimals can be useful if You have a very big fan, not in normal houses.
But the real problem is that hvac_power_percent can return a value like 33,333333333....... difficult to manage.

[swingerman]

Please check https://github.com/swingerman/ha-dual-smart-thermostat/releases/tag/v0.9.8.beta-4