Each fixture test assembled Documentation/IdStringProbe.il separately,
and ilasm writes its output next to the input: on Windows the second
test failed with a sharing violation (0x80070020) because the first
test's PEFile still had the previous output open. The probe is now
assembled once per test run from a temp copy of the .il, so the tests
share one PEFile and nothing is written into the source tree, which
also makes the per-directory .gitignore unnecessary.
Assisted-by: Claude:claude-fable-5:Claude Code