🧪 Add tests for error handling in stale-dist-check

[Hardonian]

🎯 What: The checkStaleDist logic had untestable try/catch blocks masking filesystem interactions (e.g., throwing errors when reading directories or accessing file stats).

📊 Coverage: Added test cases simulating unreadable directories (fs.readdirSync) and un-stat-able files (fs.statSync) simulating permission denied errors.

✨ Result: Test coverage improves by validating the catch blocks appropriately.

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PR created automatically by Jules for task 6793479984082694123 started by @Hardonian

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