* feat: add thermostat as climate entity
* feat: add bath-heater as climate entity
* refactor: climate entity
* fix: thermostat on/off
* fix: get the current fan mode
* perf: get fan level
* fix: fix climate hvac_mode
* fix: misuse of getting key or value from dict[int, any]
* style: add comments
* style: format the file based on google style
* fix: initialize _attr_hvac_modes
* feat: add heat and defog mode of ptc bath heater
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Co-authored-by: topsworld <sworldtop@gmail.com>