chore: improve item handling

[theEvilReaper]

Proposed changes

Both the game and setup code contain classes that handle item references for different use cases. In the current approach, these classes need to be instantiated. While this works, their nature is closer to that of utility classes. This pull request refactors them into utility classes using static methods, removing the need for instantiation.

Types of changes

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• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation Update (if none of the other choices apply)

Checklist

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• I have read the CONTRIBUTING.md
• I have added tests that prove my fix is effective or that my feature works
• I have added necessary documentation (if appropriate)

Further comments

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did and what alternatives you considered, etc...