Implement lint for regex::Regex compilation inside a loop

[GnomedDev]

Closes #598.

Seems like a pretty simple one, I'm not sure if I sorted out all the lint plumbing correctly because I was adding it to the existing regex pass, but seems to work. The name is a bit jank and I'm super open to suggestions for changing it.

changelog: [regex_compile_in_loop]: Added lint for Regex compilation inside loops.

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[y21]

I started reviewing this 2 days ago but then forgot to continue 😅 Overall looks great aside from a few things

[y21]

Given regex's own advice it makes me wonder if we could just have a lint for regex creations with literals outside of a static anywhere as having it in a static with LazyLock would avoid recompiling it ever again even across function calls, but I can see how that's more... controversial than just this specific pattern

[GnomedDev]

Yeah, that would be a separate (pedantic) lint should probably have an issue opened for it, but definitely not this one.