The windows-* jobs keep a separate standalone pnpm executable under
runner.temp/setup-pnpm-js. A previous job on the same self-hosted runner
can leave a locked @reflink native module there, so the next job's
pnpm/action-setup fails with EPERM during unlink before any test runs.
Suffix the destination with run_id, run_attempt, and job so every job
gets a fresh directory even when sequential jobs land on the same
runner; apply the same to the python SDK exe build. Update the pnpm
setup isolation note to record the Windows-specific destination.
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