support for modern flames orion device lights/flame only mode (#5264)
* changed off to cool for lights/flame only mode
* modified: modernflames_orion_fireplace.yaml
move climate from boolean switch to pure hvac_mode with preset
rename eco to low heat, boost to high heat
added boolean switch for power control
* fix(modernflames_orion_fireplace): remove whitespace and unnecessary scaling
- trim whitespace to solve lint error
- remove scaling of brightness, as it can auto scale when range is given
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Co-authored-by: Jason Rumney <make-all@users.noreply.github.com>