Feature request - Extension module that can run in the background

[cudeso]

( https://github.com/MISP/MISP/issues/3993 ) An extension module that can run in the background and continuously fetch updates.

For example: add an attribute to an event, choose the 'background'-extension module. Have the extension module regularly query a service for updates/changes. Whenever there's a change, the event gets updated with the new data.

The "time to run" (total run time) or "time to exit" (time to exit when no changes have been observed). Also an "exit-code" (special status seen in the service-response) should trigger exit of the extension module.