🛡️ Sentinel: [CRITICAL] Fix command option injection

[dttdrv]

🚨 Severity: CRITICAL
💡 Vulnerability: Command Option Injection in compileQueue.ts. The mainFile parameter was used directly in a latexmk shell command via the Rust worker without sanitizing malicious option flags.
🎯 Impact: Attackers could potentially pass malicious flags (like -shell-escape) to the latexmk binary to execute arbitrary commands.
🔧 Fix: Explicitly validated that the mainFile input does not start with a hyphen (-).
✅ Verification: Confirmed via tests and manual source inspection. Added learning to .jules/sentinel.md.

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PR created automatically by Jules for task 4124323496254008622 started by @dttdrv

[google-labs-jules]

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