Add NodeStatus record, IClusterNodeProvider interface, and AkkaClusterNodeProvider
that queries Akka cluster membership for all site-role nodes. HealthReportSender
populates ClusterNodes before each report. UI shows a row per node with
hostname, Online/Offline badge, and Primary/Standby badge. Falls back to
single-node display if ClusterNodes is not populated.
New fields in SiteHealthReport: NodeHostname, DataConnectionEndpoints
(primary/secondary), DataConnectionTagQuality (good/bad/uncertain),
ParkedMessageCount. New collector methods to populate them.
Health dashboard redesigned to match mockup: Nodes | Data Connections
(with per-connection tag quality) | Instances + S&F Buffers | Error
Counts + Parked Messages. Site names resolved from repository.
Both nodes of a site cluster were sending health reports. The standby
node (without the DeploymentManager singleton) reported 0 instances and
no connections, overwriting the active node's data in the aggregator.
Added IsActiveNode flag to ISiteHealthCollector, set by
DeploymentManagerActor on PreStart/PostStop. HealthReportSender skips
sending when the node is not active. Also ensured EnsureDclConnections
is called during startup batch creation so data connections survive
container restarts.
Wired ISiteHealthCollector calls for script errors (ScriptExecutionActor),
alarm eval errors (AlarmActor), dead letters (DeadLetterMonitorActor), and
S&F buffer depth placeholder. Added instance count tracking (deployed/
enabled/disabled) to SiteHealthReport via DeploymentManagerActor. Updated
Health Dashboard UI to show instance counts per site. All metrics flow
through the existing health report pipeline via ClusterClient.
