Thermostat service
### Device Model

HeaterCoolor service vs Thermostat service

### Is there an existing issue for this?

- [X] I have searched the existing issues and did not find an existing issue.

### Supported by Zigbee2MQTT?

- [X] Device is supported by Zigbee2MQTT

### Missing features / functionality

Nothing is missing, just inquiring about the finer details of exposing thermostat services to HomeKit.

### HomeKit Services and Characteristics

HMServiceTypeHeaterCooler
HMServiceTypeThermostat

### Exposes information from Zigbee2MQTT

```json
n/a
```


### Additional information / Other remarks

I'm curious if the properties exposed by Zigbee2MQTT define what "type" of thermostat Z2M creates for HomeKit?

For example, I have a thermostat which is a full feature (heating and cooling) thermostat, but I only use it connected to a furnace. (You helped me expose it in HomeKit by hiding the occupied_cooling_setpoint property.)

I'm not sure about the older Thermostat service, but I believe the default modes for the newer HeaterCooler service are AUTO, COOL, HEAT and OFF. Is there a way to hide other properties which then cause Z2M to reveal the Thermostat to HomeKit as just HEAT?

From researching, I gather that you can define specifically which modes to present, and can turn off unnecessary ones. It is locked to all four modes.

Is there any way to allow that selection to be made, or would it be very complicated? I have several actual heat only thermostats which still show all four modes. Also, I would love to eliminate AUTO entirely, always, because I I don't care for the way it works and just find it to be clutter.

I gather it is quicker and easier to interact with a heat-only Thermostat if HEAT is the only mode presented. (The widget displays differently.)

Thanks for your work on this plugin! This is more of a refinement curiosity, because everything already works perfectly!