🛡️ Sentinel: [CRITICAL] Fix Local Code Execution via Git Configuration

[tachyon-beep]

🚨 Severity: CRITICAL
💡 Vulnerability: Git commands executed by subprocess without explicit isolation will respect local .git/config files, allowing an attacker to run arbitrary code on the scanning machine when an untrusted repository is parsed.
🎯 Impact: Analyzing an untrusted repository could lead to arbitrary local code execution via the core.fsmonitor git configuration.
🔧 Fix: Always explicitly disable dangerous config variables when executing git commands in Python by injecting ("-c", "core.fsmonitor=false") into the argument list of subprocess.run().
✅ Verification: Verified by unit tests to make sure that the injected arguments are present in the underlying subprocess execution. Tested codebase with make test successfully.

Also added an entry in .jules/sentinel.md to document the learning.

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PR created automatically by Jules for task 13295454441535042016 started by @tachyon-beep

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