Obsolete climate.turn_on /climate.turn_off through using hvac_mode

[linux-guru-com]

Is your feature request related to a problem? Please describe. This integration obviously needs an additional service call climate.turn_on to finally turn on the device. (Addon-) Integration(s) such as scheduler-card @ do not support this and state, that this is also no common practice within Home Assistant (which I don't dare to judge).

Describe the solution you'd like hvac_mode already supports all operational modes as well as the "off" state. This should met all technical requirements for operation and obsolete the additional service call. So the final solution would be, to start the device automatically by selecting any other hvac_mode than "off" and switching it off if selecting the latter.

Describe alternatives you've considered I do currently work around this issue (in terms of automations) with having different scheduler scripts for turning on (scripted approach via scheduler-card) and turning off (simple automation containing the climate.turn_off service call) the device, which is some overhead.

Additional context ./.