engine: Service timeout shutdown

[DanCodedThis]

Closes #1896

• Adds new cli option: IDLE_TIMEOUT_SECONDS with default value of 18000 (5 hours)
• Adds new timeout_signal fn is a execution service
• The function is done similar to the session expiration and other shutdown signals
• The function is then used in tokio select of graceful shutdown of the axum::serve in main
• Adds an expiration time test
• Interval and idle timeout now are different numbers, to avoid bugs written below

[github-actions]

✅ SLT Targeted Testing: No relevant SLT tests found for the changes in this PR. No testing required.

[DanCodedThis]

The timer check interval and the idle timeout should be two different numbers, where if one queries some time ago and then on the second looses his last session when the check happens it shouldn't shut down since the use was recent

[github-actions]

✅ SLT Targeted Testing: No relevant SLT tests found for the changes in this PR. No testing required.