Add support for 22+ case class in format macros

[Iilun]

Pull Request Checklist

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• Have you added copyright headers to new files?
• Have you updated the documentation?
• Have you added tests for any changed functionality?

Fixes

Fixes #3

Purpose

This PR introduces support for macros for case classes with more than 22 fields.

Background Context

The existing macro could not handle case classes with more than 22 fields and failed with an error No unapply or unapplySeq function found for ....

Implementation choices

My goal in this implementation was to keep all existing code paths exactly the same, and for the new approach, take inspiration from the play-json-extensions macro.

This was to ensure that if someone used custom apply / unapply, it would not be impacted, and my new implementation only starts when the aforementioned error would otherwise have surfaced, only introducing a new behavior, and not affecting existing code.

This does mean that I had to duplicate the test coverage, since the code paths for case class <22 and 22+ are different. This produces a quite heavy diff, I am unsure what strategy to adopt here.

I also avoided messing too much with the utility CaseClass class, as its code is not easily readable, and only edited it to reuse existing code.

If this choice does not meet the repo criteria, I will happily refactor this, to have a uniform code path if required (however I am afraid of regressions with such an approach, since the previous macro approach had a lot of quirks)

Docs

I searched the documentation, but it mentioned that case class were supported, so I wasn't sure what to add to it, left it as is for now.

Thank you for your feedback !