feat(audit): M5.2 per-node stuck-count KPIs (T6) — repo per-node aggregation, actor message pair, CentralUI tiles

src/ZB.MOM.WW.ScadaBridge.Commons/Interfaces/Repositories/INotificationOutboxRepository.cs

@@ -100,6 +100,19 @@ public interface INotificationOutboxRepository
     Task<IReadOnlyList<SiteNotificationKpiSnapshot>> ComputePerSiteKpisAsync(
         DateTimeOffset stuckCutoff, DateTimeOffset deliveredSince, CancellationToken cancellationToken = default);
 
+    /// <summary>
+    /// Computes a point-in-time <see cref="NodeNotificationKpiSnapshot"/> per originating node.
+    /// Nodes with no notification rows at all are omitted; rows with a <c>NULL</c>
+    /// <c>SourceNode</c> are excluded. The stuck and delivered cutoffs are supplied by the
+    /// caller; the current time used for <c>OldestPendingAge</c> is captured inside the method.
+    /// </summary>
+    /// <param name="stuckCutoff">The time threshold for marking notifications as stuck.</param>
+    /// <param name="deliveredSince">The time threshold for counting delivered notifications.</param>
+    /// <param name="cancellationToken">Cancellation token.</param>
+    /// <returns>A list of per-node KPI snapshots, ordered by node name.</returns>
+    Task<IReadOnlyList<NodeNotificationKpiSnapshot>> ComputePerNodeKpisAsync(
+        DateTimeOffset stuckCutoff, DateTimeOffset deliveredSince, CancellationToken cancellationToken = default);
+
     /// <summary>
     /// Persists pending changes tracked on the underlying context. Use this when staging
     /// multiple changes for a single commit; the individual mutating methods on this