Improve type hints in apple_tv media player

[epenet]

Proposed change

Improve type hints in apple_tv media player

As draft until #77941 is confirmed

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• 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)
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• This PR fixes or closes issue: fixes #
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[probot-home-assistant]

Hey there @postlund, mind taking a look at this pull request as it has been labeled with an integration (apple_tv) you are listed as a code owner for? Thanks!
_{^{(message by CodeOwnersMention)}}

[cdce8p]

Seems like MediaClass isn't imported in media_player.__init__.

[epenet]

I was going to rebase over the cast PR. Since that PR is delayed I have added it here (shouldn't cause a conflict).