Add entity options to entity registry

[emontnemery]

Proposed change

Add entity options to entity registry.

This could for example be the wanted unit of a sensor or weather entity, the minimum brightness of a light or the maximum volume of a speaker.

Entity options should be indexed by domain, e.g. options["light"]["minimum_brightness"]
A new helper method for setting options, EntityRegistry.async_update_entity_options, is added to the entity registry.

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New integration (thank you!)
• New feature (which adds functionality to an existing integration)
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

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• This PR fixes or closes issue: fixes #
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[balloob]

let's move this to a new method, update_entity_options(domain, options)

[droberg]

Would this functionality add the possibility to have for example calibration values as entity options.

Also, would this make #64315 redundant ?

[emontnemery]

@droberg I think an option for configuring the wanted precision would be a welcome addition for sensor, not sure how well that maps to the resolution options for the Maxim DS18B20 though.