GraalPy support

[steve-s]

This makes jiter work on GraalPy except for test_python_parse_numeric, for which GraalPy will need to provide missing API _PyLong_FromByteArray.

Update: the API is now implemented in GraalPy main branch.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 94.55%. Comparing base (754395c) to head (3cc2e62).
Report is 2 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #135   +/-   ##
=======================================
  Coverage   94.55%   94.55%           
=======================================
  Files          12       12           
  Lines        2039     2039           
=======================================
  Hits         1928     1928           
  Misses        111      111           

Files with missing lines	Coverage Δ
crates/jiter/src/py_string_cache.rs	97.05% <ø> (ø)

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[codspeed-hq]

CodSpeed Performance Report

Merging #135 will not alter performance

_{Comparing steve-s:graalpy (3cc2e62) with main (754395c)}

Summary

✅ 73 untouched benchmarks

[samuelcolvin]

thank so much.