Use IntFlag for EntityFeature

[epenet]

Proposed change

Replace IntEnum with IntFlag for ***EntityFeature

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)
• Deprecation (breaking change to happen in the future)
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

Additional information

• This PR fixes or closes issue: fixes #
• This PR is related to issue:
• Link to documentation pull request:

Checklist

• The code change is tested and works locally.
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• There is no commented out code in this PR.
• I have followed the development checklist
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• Tests have been added to verify that the new code works.

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[uvjustin]

Is it worth doing this by platform so we can also change the type hints that use int in the individual components?

[epenet]

I was planning further tweaks in a follow-up PR (pylint and individual components).
There are so many components to adjust that I think it's better to not adjust components at the same time as the base platform.

[epenet]

Is it worth doing this by platform so we can also change the type hints that use int in the individual components?

I normally try to avoid adjusting components at the same time as platform, as it makes it harder to review

[epenet]

@uvjustin I actually revert the type hints for now, to keep this PR smaller.
We can look at the type hints in a follow-up PR.

[frenck]

LGTM, Thanks @epenet 👍