Add transceiver status to wicket

[bnaecker]

• Make the current inventory specific to MGS
• Add per-switch transceiver list to the inventory as well
• Fetch transceiver state periodically in wicketd
• Draw transceiver details in the wicket inventory panel
• Fixes Wicket could show basic transceiver status during rack setup #6710

[bnaecker]

Here is a screenshot showing the normal, expected contents when a transceiver is all working correctly.

There are a few ways the transceivers can go off the rails, but the most common is that we simply have no light on one side or the other. Below is a screenshot of what that will look like if we have transmit power below some minimum threshold. (I simulated this by disabling the link via Dendrite.) We'll have similarly-colored warnings for all the monitors, if they're outside some expected range.

This last part isn't perfect. One could argue that we shouldn't consider it unusual if there's no Tx power when the link is disabled entirely -- we shouldn't be transmitting anything. There are also some other flags and warnings we can print, such as whether we have a Tx fault, or if the module can recover a clock from the Rx signal. I'm open to adding these in later PRs if we think they'll be useful.

[sunshowers]

Thank you! Just a few questions.

[bnaecker]

I'd like to test this one more time on a system with actual transceivers, since 1d87e93 updated the logic around UI formatting quite a bit. Will take this for another lap when a system opens up in the lab.

[bnaecker]

Ok, running the latest on dublin shows that things still look reasonable from a UI perspective. I've updated a few pieces of specific wording, like "software control" instead of "software override" or "unsupported" instead of "unavailable". But otherwise, this is the same.

[bnaecker]

So funny enough, the temp and voltage being unsupported uncovered a bug, thanks to @rmustacc. See oxidecomputer/transceiver-control#339, which is fixed in oxidecomputer/transceiver-control#341. That will get picked up by this code automatically next time we update the transceiver-control crate, no need to block this on that right now.

[sunshowers]

Awesome, thank you so much for working through the comments!