src: add an option to make compile cache path relative

[Aditi-1400]

Adds an option (NODE_COMPILE_CACHE_RELATIVE_PATH) for the built-in compile cache to encode the hashes with relative file paths. On enabling the option,
the source directory along with cache directory can be bundled and moved, and the cache continues to work.

When enabled, paths encoded in hash are relative to compile cache directory.

Fixes: #58755

Thanks @joyeecheung for all the help :)

[codecov]

Codecov Report

Attention: Patch coverage is 67.79661% with 19 lines in your changes missing coverage. Please review.

Project coverage is 90.09%. Comparing base (85e8cc6) to head (0d4fb87).
Report is 58 commits behind head on main.

Files with missing lines	Patch %	Lines
src/compile_cache.cc	64.00%	9 Missing and 9 partials ⚠️
src/env.cc	88.88%	0 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #58797      +/-   ##
==========================================
- Coverage   90.16%   90.09%   -0.07%     
==========================================
  Files         636      640       +4     
  Lines      188061   188341     +280     
  Branches    36899    36927      +28     
==========================================
+ Hits       169561   169692     +131     
- Misses      11245    11363     +118     
- Partials     7255     7286      +31     

Files with missing lines	Coverage Δ
src/compile_cache.h	100.00% <ø> (ø)
src/node_file.h	78.43% <ø> (ø)
src/env.cc	80.98% <88.88%> (+0.16%)	⬆️
src/compile_cache.cc	78.18% <64.00%> (-2.60%)	⬇️

... and 76 files with indirect coverage changes

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[joyeecheung]

Can you add some integration to module.enableCompileCache() as well? I think having it in options bag when the first argument is an object might work well enough. The path can be options.path in that case.

[joyeecheung]

I wonder if "relative" is more of an implementation detail, what we really want to allow is "portable" compile cache (i.e. you can move the code and the compile cache to a different base directory, the cache will still be hit as long as they maintain the same directory structure) So maybe NODE_COMPILE_CACHE_PORTABLE=0 would be more intuitive and we can explain about the directory structure with an example in the docs.

[joyeecheung]

Also, please add some documentation to the Module compile cache section in module.md as well.

[joyeecheung]

This is something we can just compute once and store in the CompileCacheHandler instance. This is currently being repeatedly computed for every path match even though it's the same every time.

[joyeecheung]

Can you add some tests for module.getCompileCacheDir() as well? I think it should return a relative path (from process.cwd()?) in that case.