🛡️ Sentinel: [HIGH] Fix DoS vulnerability in shell and network operations

[thirdbase1]

🚨 Severity: HIGH
💡 Vulnerability: Agent operations lacked strict boundaries. Shell executions via ShellTool did not enforce timeouts or memory limits, and AgentConnector network requests lacked connection timeouts. This exposed the system to DoS and resource exhaustion attacks via hanging processes, massive output buffers, or stalled API endpoints.
🎯 Impact: An attacker or a malfunctioning agent could cause the system to hang indefinitely or consume excessive memory, leading to a Denial of Service (DoS) and bringing down the execution environment.
🔧 Fix: Enforced a 30-second timeout and a 1MB output buffer limit on shell command executions (execAsync). Enforced a 30-second connection timeout on external API client instances (axios.create).
✅ Verification: Run npm run build and npm run test to verify the execution of tools still behaves as expected and no tests are broken.

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PR created automatically by Jules for task 12955045728415150609 started by @thirdbase1

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