Editing Proxyd backend healthy

In [[proxyd]] a backend is considered healthy if it meets the following criteria
* Not [[banned]]
* Avg 1-min moving window [[error rate]] ≤ [[configurable threshold]]
* Avg 1-min moving window latency ≤ configurable threshold
* [[Peer count]] ≥ configurable threshold
* [[Latest block]] lag ≤ [[configurable threshold]]
* [[:ast state update]] ≤ configurable threshold
* Not currently [[syncing]]



{{proxyd}}