[clang-tools-extra] [clang-tidy] add new check readability-enum-initial-value (PR #86129)

[Piotr Zegar via cfe-commits]

https://github.com/PiotrZSL requested changes to this pull request.

Overall looks fine.
Some minor style issues.

Try getting rid of findNextTokenSkippingComments, and maybe just jump to begin() + token width

https://github.com/llvm/llvm-project/pull/86129