Wire the operator Alarm Summary page to the transient per-site live alarm
cache (ISiteAlarmLiveCache, T4). Live-cache-first: on site select the page
subscribes and rebuilds rows/rollup from near-real-time onChanged deltas; the
15s poll is kept untouched as the authority for NotReporting and as the
safety net whenever the cache is not live (pre-seed or degraded stream). Both
paths mutate shared state only via the Blazor dispatcher, so they never race,
and each rebuild is an idempotent snapshot.
- IAlarmSummaryService.BuildFromLiveAlarms: flattens a live AlarmStateChanged
snapshot to AlarmSummaryRows with the same deterministic instance-then-name
sort as GetSiteAlarmsAsync; NotReporting always empty on the live path.
- AlarmSummary.razor: inject ISiteAlarmLiveCache; subscribe on select,
re-subscribe on site change, unsubscribe on leave + Dispose.
- Tests: service BuildFromLiveAlarms flatten/sort/empty; page subscribe,
poll-fallback render, onChanged rebuild, unsubscribe on leave/change/dispose.
Claude-Session: https://claude.ai/code/session_01MtdgwpEeCUn6cUA5f1LMPj
Joseph Doherty