🛡️ Sentinel: Secure tool resolution

[acebytes]

🚨 Severity: LOW / Defense-in-depth

💡 Vulnerability: The toolExists helper function used string interpolation in a /bin/bash wrapper to execute /usr/bin/which. While the input to this function was not currently user-controlled, relying on string interpolation in a shell string is an insecure pattern that could lead to command injection if the input surface area expands.

🎯 Impact: A malicious user or downstream input providing arbitrary strings (e.g., rm -rf /;) could have executed unauthorized code as the application's user identity.

🔧 Fix: Refactored toolExists(_:) to execute /usr/bin/which directly as the Process.executableURL, and passed the dynamic tool input securely as an element in the Process.arguments array. This completely bypasses the shell and prevents execution of injected commands. Unnecessary standard streams were also properly mapped to FileHandle.nullDevice to prevent resource leakage.

✅ Verification:

• Attempted to run the test suite locally (swift / xcodebuild missing in environment, manually reviewed changes).
• The updated code uses the correct /usr/bin/which absolute path and explicitly checks terminationStatus == 0.

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PR created automatically by Jules for task 7278744798030084859 started by @acebytes

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[chatgpt-codex-connector]

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[chatgpt-codex-connector]

Set deterministic PATH for tool existence checks

This refactor invokes /usr/bin/which without setting process.environment, so it now depends on whatever PATH the app inherited. On macOS app launches (especially from Finder), PATH commonly omits /opt/homebrew/bin and /usr/local/bin, which makes toolExists("brew")/toolExists("npm") falsely return false even when tools are installed. Because resolvedPaths immediately continues when toolExists fails, probed categories can be skipped entirely and their fallback paths are never reached. Set a controlled PATH/HOME (like shell(_:) does) before process.run() to avoid this regression.

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