Steps to reproduce

CC @dcharkes, this is the last of the build-related problems I've run into for Native Assets (I think anyways...)

I'm happy to PR a fix for this, I just would like clarification on which of the 2 approaches listed below (or something else) we would like to go with in order to fix this.

Currently, CCompilerConfig is created this way on macOS:

This breaks under Nix on macOS when the xcrun is provided via Nix, as ld + ar are not present at the location expected above.

Expected results

CCompilerConfig should be created via either:

1. (Simpler + likely more correct) use xcrun --find <binary-name> to find clang, ld, and ar
   i. Based on CLI experimentation this produces correct results in both Nix + non-Nix environments on macOS
2. Looking on PATH for clang and then use that to find its associated ld + ar (like is done on Linux)

Actual results

Build fails due to ld + ar not existing at the expected location.

Logs

ERROR: Build input for <project-name> contains errors
- BuildInput.config.code.cCompiler.linker (/nix/store/538b7kiga26rcxpqjspyn4r8wg32fmgh-clang-20.1.6/bin/ld) does not exist as a file.
- BuildInput.config.code.cCompiler.archiver (/nix/store/538b7kiga26rcxpqjspyn4r8wg32fmgh-clang-20.1.6/bin/ar) does not exist as a file.