The denormalised projection was never written by the alerts code
path, so the dashboard's OPEN ALERTS card and the per-host alerts
column always read 0 regardless of how many alerts were open.
fleet.GetStats sums hosts.open_alert_count; if it never moves, the
card is decoration.
Add refreshHostOpenAlertCount that recomputes from the alerts table
(self-healing — no +/- bookkeeping to drift). Call it after the
commit in RaiseOrTouch when a row was inserted, after Resolve, and
after AutoResolve.
Caught during the live sweep: a synthetic critical raised the count
to 1, but resolving it left the dashboard reading '1 unresolved'
indefinitely.
steve