feat: build in stable rust

[LoricAndre]

Hi, thank you for your work on this project (and on blink.cmp).

I'd like to use your matcher in skim, but I'd also like to retain compilation using stable rustc.
This is what was needed for it to work, I'm not a huge fan of the Appendable impl but it seemed okay to panic there.

[saghen]

That'd be neat! Unfortunately, if you remove the SIMD smith waterman, I wouldn't imagine the scalar matcher is that quick (benchmarks welcome though). I'm looking into porting all the SIMD to use intrinsics so that it'll be availabe on stable rust, but it's a ways out since I'm combining those changes with a large rewrite of the smith waterman logic. You could use nucleo for now which is still quite quick if you don't need typo resistance.

[LoricAndre]

Typo resistance is exactly what I'm looking for 😅

As far as benchmarks go, my benchmark script reported this matcher to be as fast as skim's current one in a realist-ish test. I just released a version that uses the latest pushed crate, feature-gating it on my side so that library users can still use skim with stable rust, but without this matcher.

[saghen]

Nice! Linking that benchmark for anyone else who wants to look: skim-rs/skim#891

I'm actually quite surprised it kept up with max_typos: Some(2)! Fyi, for blink.cmp, I set the max_typos based on the length of the keyword. https://github.com/saghen/blink.cmp/blob/main/lua/blink/cmp/config/fuzzy.lua#L43

[LoricAndre]

I was really pleasantly surprised to see how easy it was to integrate it, I set the default to 2, I'll probably make it smarter in the future but 2 seems reasonable IMO.