recordTaskResult reset the failure counters on a successful poll but left
LastErrorAt/LastErrorMessage/LastErrorCategory in place forever. The
connections aggregator surfaces that field as a live error banner on
Settings -> Infrastructure and derives the Unauthorized state from it, so
one transient cluster outage (or startup blip) pinned a red "no healthy
nodes available" banner onto a connection that polls fine, and a single
past 401 could pin a healthy connection to Unauthorized.
LastError now means "current outstanding failure since the last success":
recorded on failure, cleared on success. Connections that are genuinely
failing (no successful poll) keep their banner.
Refs #1493
rcourtman
6eaea2fc3a