fix(comm): shared oldest-Up ActiveNodeEvaluator in Communication; Host evaluator delegates (plan R2-02 T1)

src/ZB.MOM.WW.ScadaBridge.Host/Health/ClusterActivityEvaluator.cs

@@ -13,23 +13,15 @@ namespace ZB.MOM.WW.ScadaBridge.Host.Health;
 /// </summary>
 public static class ClusterActivityEvaluator
 {
-    /// <summary>True when self is Up and no other Up member (in the role scope) is older.</summary>
+    /// <summary>True when self is Up and no other Up member (in the role scope) is older.
+    /// Delegates to the shared <see cref="Communication.ClusterState.ActiveNodeEvaluator"/> —
+    /// one implementation for the delivery gate, the resync authority checks, and the
+    /// heartbeat IsActive stamp (review 02 round 2, N1).</summary>
     /// <param name="cluster">The Akka cluster to evaluate.</param>
     /// <param name="role">Optional role scope; when set, only members with this role are considered.</param>
     /// <returns><c>true</c> when self is Up and the oldest Up member in the role scope.</returns>
-    public static bool SelfIsOldest(Cluster cluster, string? role = null)
-    {
-        var self = cluster.SelfMember;
-        if (self.Status != MemberStatus.Up)
-            return false;
-        if (role != null && !self.HasRole(role))
-            return false;
-
-        return cluster.State.Members
-            .Where(m => m.Status == MemberStatus.Up)
-            .Where(m => role == null || m.HasRole(role))
-            .All(m => m.UniqueAddress.Equals(self.UniqueAddress) || self.IsOlderThan(m));
-    }
+    public static bool SelfIsOldest(Cluster cluster, string? role = null) =>
+        Communication.ClusterState.ActiveNodeEvaluator.SelfIsOldestUp(cluster, role);
 
     /// <summary>The oldest Up member in the role scope, or null while none is Up. Used for Primary/Standby labelling.</summary>
     /// <param name="cluster">The Akka cluster to evaluate.</param>