Update CONTRIBUTING.md

[zaicruvoir1rominet]

Summary

Update CONTRIBUTING.md to make the PR process smoother for newcomers.
Issue: #1084

Test Plan

None

[zaicruvoir1rominet]

The process is not complete yet:

• Following these steps doesn't seem to place the built libcst.native at the correct spot, resulting in libcst.native import errors when using hatch run test.
• Pyre seems to have a configuration problem when using hatch run lint, resulting in traces far different from the main libcst GitHub CI

Any thoughts on how to solve this ?
(For my PR, I just ditched hatch altogether, using the pytproject.toml as base ; getting the libcst.native from a compiled version)

[zsol]

Thank you, this is great!

[zsol]

Oh whoops I missed your questions. Let me see if I can figure it out tomorrow

[zsol]

I can't repro either of the problems you mention if I follow the instructions. FWIW I'm running hatch v1.10.0 on MacOS and I can see

  Copying rust artifact from native/target/debug/liblibcst_native.dylib to libcst/native.cpython-310-darwin.so

in the output of hatch -vvv env create.

As for the typechecking issue, hatch run lint doesn't run the type checker, hatch run typecheck does. Maybe worth adding that to the doc