Discuss what to do to the Eiger on a stop

Currently when the Eiger is stopped we assume this is because there has been an error and so we disarm and clean up the detector. However, we could have stopped because of a `pause()` or a from a suspender. So far this has never happened as we run only unattended and don't use suspenders.

For a `pause` we may not want to stop the detector. `stop` does take a `success` param that we can probably use to determine this. It would also be nice if we had similar behavior across all detectors and so we should discuss this with core

## Acceptance Criteria
* We discuss what we would like to do on `stop` more generally
* Decision made and documented
* Tickets spawned if required