Expose heating mode for NodOn SIN-4-FP-21 and Legrand cable outlet

[TheJulianJES]

We should expose the heating/wire mode for the NodOn SIN-4-FP-21 and Legrand cable outlet to Home Assistant.
Related PRs:

• Add initial NodOn SIN-4-FP-21 (Adeo SIN-4-FP-21_EQU) quirk #3364
• Improve Legrand 064882 cable outlet heat mode #3031

Concerns were raised that we would not conform to Home Assistant standards by exposing the heating/wire mode of the devices as a select entity. Rather, we should consider having a climate entity. The heating mode would replace the automatically discovered on/off switch entity and the enums would be shown as heating presets.

Zigbee2MQTT just exposes an enum, similar to what's proposed in #3364.

The Legrand device is marketed as a smart power outlet with power consumption monitoring. The NodOn device is a shelly-like module with a full focus on being connected to an electric heater. Both devices seem to be similar software-wise.
For the Legrand device, it would be weird removing the existing switch entity for users only utilizing the smart on/off functionality for a non-heating device.

There's been no decision on what we can/want to do yet

[vinc]

I've been following the PR for the NodOn SIN-4-FP-21 that I installed on some heaters in my house. I successfully validated the current switch to turn my heaters on or off but a simple solution to switch between the different modes (comfort, eco, off, etc) would be really useful for my usage!

[luke7101]

Just my 2 cents, for me the whole point on the Legrand is its ability to totally power off the heater when it isn't needed, and use the pilot wire orders when needed.
Why don't I just use the off pilot wire order ? Because it can be overridden by a heater physical button, and kids do like to play with buttons... 😅 This way no one can force it on when it's physically powered off.