The test was failing intermittently on Windows with "expected: <1> but
was: <2>" because it was searching the entire project scope where files
from other concurrent tests could interfere.

Changes:
- Use unique timestamped folder name to avoid conflicts
- Narrow search scope to only the test's specific folder
- Add comments explaining the fix

This ensures test isolation when running in parallel.

Fixes #3490

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