Max Weinbach7/7/2026, 2:09:06 PM

The fixture mapped POSIX scripts to 'cmd /c' on Windows, so 6/10 tests failed
on this host (blocking the Phase-6 CI matrix flip). Children are now inline
'bun -e' scripts — identical semantics on every OS, no shell dialect — while
every behavioral assertion (TIMEOUT→124, ABORT_ERR→130, ENOENT, maxBuffer
truncation, env replacement, capture) is preserved. Green on Windows now;
still green on POSIX. Migration row 18.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

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