Add Explorer EVO 3 (model 2374) water heater support and 62°C setpoint fallback

[StefanWokusch]

Summary

This adds support for Cozytouch model 2374, which is currently exposed as Unknown product (2374).

For this model, the integration now:

• maps the device as Explorer EVO 3 (260L)
• treats it as a WATER_HEATER
• applies a model-specific fallback max of 62.0°C for the standard target_temperature and target_temperature_dhw number entities when Cozytouch does not expose the dynamic max capability

Why

On this device, the standard Home Assistant setpoint entity was limited to 60°C, while:

• the manufacturer app allows at least 62°C
• the device datasheet indicates a WP-mode setpoint range up to 62°C

The current integration falls back to 60.0 in number.py when no higher max value is provided by Cozytouch. For model 2374, that fallback appears to be too low.

Notes

This change is intentionally narrow:

• only modelId == 2374 is affected
• only the standard target_temperature / target_temperature_dhw fallback max is changed
• the separate raw 105906 / 105907 targets are left untouched

Validation

Validated locally by:

• confirming live behavior against a real Explorer EVO 3 installation
• checking that model 2374 was previously treated as unknown
• running python -m compileall custom_components/cozytouch