Refactor squeezebox integration media_player to use coordinator

[rajlaud]

Proposed change

This refactors the media_player platform of the squeezebox integration to use a coordinator. While it doesn't change any functionality now, it will allow us to also store player-related information in sensors (see, e.g., #127425 (comment)).

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• Dependency upgrade
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• Breaking change (fix/feature causing existing functionality to break)
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• This PR fixes or closes issue: fixes #
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[home-assistant]

Hey there @pssc, @peteS-UK, mind taking a look at this pull request as it has been labeled with an integration (squeezebox) you are listed as a code owner for? Thanks!

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[rajlaud]

@pssc and @peteS-UK , this works locally for me and passes all the tests. Still, would appreciate your eyes and some testing on your local setup to make sure this doesn't break anything.