Consider adding timeout value to script execution

[nafai]

As seen in #2202, presenting in the agent console message Run commands can't execute, already busy.

By running a script that pauses for any reason (waiting on stdin, waiting on an interactive window, etc), an agent can get "stuck" and not process any other scripts you try to send it. An agent will remain in this state until the service is restarted, running agentupdate, etc.

Please consider adding a timeout value for script execution in config.json. Even a long timeout (1800/3600 secs as a default value) would be preferable to an indefinite timeout.

Alternatives could include adding the timeout as another field in the Run Commands dialog, or to just launch multiple scripts in parallel and not care if they ever finish executing.