fix(opcua): #855 review 2 — frozen replay skips non-live conditions; per-hop ACL resolution; drain never inline

- QueueFrozenReplay's verdict refuses a condition a deploy removed or replaced
  since the cut (Server-object and folder), so the cut path cannot replay a
  ghost or judge a replaced scripted alarm on its old folder.
- DeliverToNotifierItems resolves the #826 decision's item-independent part
  (live condition, notifier check, scopes) once per hop; only the grant and
  SDK role checks stay per item.
- A deferred delivery's drain starts on the pool, never inline under Lock.
- Test: a condition removed between the cut and its replay (folder + Server
  object).

Claude-Session: https://claude.ai/code/session_01GT67AD99zQQqpLCVm3p7xk

src/Server/ZB.MOM.WW.OtOpcUa.OpcUaServer/OtOpcUaNodeManager.cs

@@ -1539,13 +1539,19 @@ public sealed class OtOpcUaNodeManager : CustomNodeManager2, INodeManager3
             return;
         }
 
+        DeferredConditionReports queue;
         lock (_eventReportGate)
         {
-            var queue = new DeferredConditionReports();
+            queue = new DeferredConditionReports();
             _deferredReports[condition] = queue;
             CountDeferred(+1, condition);
-            _ = DrainDeferredAsync(condition, queue, delivery.AsTask());
         }
+
+        // #855 review 2: started on the pool, never inline. The suspended delivery may complete between the check above and
+        // here; an inline drain would then run (and end the episode, and clear cuts over every item gate) on this thread,
+        // under Lock. The queue is registered first, so this condition's later reports wait behind it either way.
+        var inFlight = delivery.AsTask();
+        _ = Task.Run(() => DrainDeferredAsync(condition, queue, inFlight));
     }
 
     /// <summary>Queues a later event behind a condition's deferred one, coalescing past the budget. Under the gate.</summary>
@@ -1719,13 +1725,33 @@ public sealed class OtOpcUaNodeManager : CustomNodeManager2, INodeManager3
     private void DeliverToNotifierItems(MonitoredNode2 monitored, IFilterTarget e)
     {
         var deferred = e is ConditionEventSnapshot { Deferred: true } d ? d : null;
+
+        // #855 review 2: the #826 decision's item-independent part — the live condition, whether this notifier is still a
+        // legitimate notifier of it, and its visibility scopes — is resolved ONCE per hop, not per item (it is what
+        // IsNotifierEventVisibleTo resolves for an item attached here). Only the grant check and the SDK's role check
+        // remain per item.
+        var enforced = AclEnforced;
+        List<NodeId>? scopes = null;
+        if (enforced)
+        {
+            if (EventConditionOf(e) is not { } named
+                || !_alarmConditions.TryGetValue(MapKey(named.NodeId), out var live)
+                || !IsLiveNotifierOf(live, monitored.Node))
+            {
+                return; // fail closed for every item on this notifier
+            }
+
+            scopes = ConditionVisibilityScopes(live);
+        }
+
         foreach (var item in monitored.EventMonitoredItems.Values)
         {
             if (item is null) continue;
             try
             {
                 if (IsAuditEvent(e) && !IsAuditDeliverableTo(item)) continue;
-                if (ServiceResult.IsBad(((INodeManager3)this).ValidateEventRolePermissions(item, e))) continue;
+                if (ServiceResult.IsBad(ValidateEventRolePermissions(item, e))) continue;
+                if (scopes is not null && !IsConditionVisibleTo(item, scopes)) continue;
                 QueueConditionEventToItem(item, e, deferred, DeferredFolderDeliveryProbe);
             }
             catch (Exception ex)
@@ -6701,6 +6727,9 @@ public sealed class OtOpcUaNodeManager : CustomNodeManager2, INodeManager3
             generation,
             (item, e) =>
             {
+                // #855 review 2: never replay a condition a deploy has removed or replaced since the cut — its frozen
+                // state would be a ghost (and, with the ACL on, a replaced scripted alarm would be judged on its old folder).
+                if (ConditionOf(e) is { } frozen && !IsLiveCondition(frozen)) return false;
                 if (enforced)
                 {
                     if (ConditionOf(e) is not { } condition) return false;
@@ -6981,7 +7010,10 @@ public sealed class OtOpcUaNodeManager : CustomNodeManager2, INodeManager3
 
             DirectRefreshProbe?.Invoke(true, Monitor.IsEntered(Lock));
             // #855 review: re-decided per entry right before queueing — a deploy may have revoked since the verdicts.
-            QueueFrozenReplay(items, states, perItem, generation, (item, e) => IsDirectRefreshEventAllowed(item, e, enforced));
+            QueueFrozenReplay(
+                items, states, perItem, generation,
+                (item, e) => (ConditionOf(e) is not AlarmConditionState frozen || IsLiveCondition(frozen))
+                             && IsDirectRefreshEventAllowed(item, e, enforced));
         }
         finally
         {