Publish telemetry status on telemetry update and on heartbeat update eve...

...nts to avoid inducing heartbeat update latencies resulting in spurious telemetry link dropped detections. Makes overall state handling simpler.

Essentially we now publish on heartbeat and on telem status updates, because both are a proper change of the topic. While this might increase publications by a factor of two, it just means going from 1 Hz to 2 Hz. We still need to do this, because we do data link loss handling based on the heartbeat timeout, so we need to get every single heartbeat update immediately.