🔒 Fix Command Injection in Sandbox Setup

[TrueAlpha-spiral]

🎯 What: Fixed a command injection vulnerability when setting up the sandbox proxy in packages/cli/src/utils/sandbox.ts.
⚠️ Risk: A malicious user or an unexpected environment setup could inject arbitrary commands by polluting the config.command value that was being unsafely interpolated into an execSync command string, which is run through a shell.
🛡️ Solution: Migrated the logic from execSync to execFileSync, which prevents shell evaluation by taking arguments securely as an array: execFileSync(config.command, ['rm', '-f', SANDBOX_PROXY_NAME]). Also wrapped it in a try...catch block to handle errors silently, replacing previous behavior.

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PR created automatically by Jules for task 1508165869636238271 started by @TrueAlpha-spiral

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