core: frontend: notify when devices disconnect

Current behaviour

Currently if we lose access to a peripheral that isn't the autopilot then BlueOS generally doesn't provide any kind of consistent or obvious warning about it, so the operator may not realise until a point where it's problematically late.

In addition, issues like #2569 can be indicative of a hardware problem from a loose connection / damaged cable, which either results in unpleasant interface bugs with repeating or disappearing devices, or gets hidden by smarts that assume it's the same device but still don't provide a meaningful warning to the user.

Expected or desired behaviour

It seems worthwhile to:

try to detect if any connected device (serial, camera, ethernet, etc) drops out, and provide a notification of it
- and maybe services (wifi, internet, etc) and extensions too?
keep track of when devices last dropped out, and if it was recently and happened more than once provide a warning about potential hardware/connection issues

We could potentially create a service for this, that either monitors all devices at the hardware level, or that provides an API for device managers and drivers to give basic status/event updates with things like the name and type of a given connection (and maybe some relevant metadata if appropriate, like last recorded temperature and/or validity/status), and then the service can be in charge of the (configurable?) notifications and the repeated disconnection tracking + warning. That could optionally provide MAVLink notifications/warnings too, at the user's discretion, and could provide aggregated telemetry to provide to the user's BlueOS Cloud account so they can identify known issues with vehicles.

Prerequisites

[X] I have checked to make sure that a similar request has not already been filed or fixed.

bluerobotics / BlueOS