support blc2

[gkgoat1]

blc2 is BLC enhanced with levenshtein-encoded binary indices.

[marvinborner]

Thanks, looks good! I suppose this is inspired by blc2blc?

Could you add some tests in tests/ maybe?

[gkgoat1]

Thanks, looks good! I suppose this is inspired by blc2blc?

That, and the issue you presented in this repo concerning variable indices in lambda-8cc, which get large converting to and from BLoC.

Could you add some tests in tests/ maybe?

I added generation tests, but without access to CI I cannot test their accuracy using either blc2blc or my own Rust implementation.