🛡️ Sentinel: [MEDIUM] Replace bash shell wrapper with direct execution for docker prune

[acebytes]

🛡️ Sentinel: [MEDIUM] Replace bash shell wrapper with direct Process execution for docker prune

🚨 Severity: MEDIUM
💡 Vulnerability: Executing external commands via /bin/bash -c (specifically docker system prune in dockerPrune()) introduces potential command injection risks if user input is ever incorporated, and unnecessarily violates the principle of least privilege.
🎯 Impact: Prevents future command injection vulnerabilities and establishes a secure execution pattern natively within the Swift Process API.
🔧 Fix: Changed the Process execution from /bin/bash -c "docker system prune -f 2>&1" to direct execution using /usr/bin/env with arguments ["docker", "system", "prune", "-f"]. The shell redirection (2>&1) was securely replicated by assigning the same Pipe instance to both the standardOutput and standardError properties natively. Added a learning journal entry regarding this mechanism in .jules/sentinel.md.
✅ Verification: Verify by running the application and initiating a Docker prune. The docker system prune command should execute identically and capture both standard and error outputs, but without invoking an intermediate Bash shell.

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PR created automatically by Jules for task 2674030477487046103 started by @acebytes

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