Online status ("Up") flickering

[easybe]

At least with our deployment, even though my device is obviously communicating with the server (as indicated by "Last seen") the "Up" status turns red from time to time.

[b-rowan]

The up value just checks if the device has communicated within whatever value is set for poll time on that device. We could change it to check against default poll time, plus a couple of seconds.

[easybe]

I think there should be quite a margin, maybe in percent? Eventually, we plan to use a poll time of 1 day or more, so we should keep that in mind.

[b-rowan]

I think anywhere from 1.2 - 1.5X the poll time would be fine. We could also make that configurable pretty easily, just add it to the pydantic settings, something like poll_time_online_multiplier?

[easybe]

I don't think it should be configurable. It should "just work" for short and long intervals.