fix(dcl): advance the session generation on same-adapter reconnect and session-scope MxGateway subscription ids (review 2026-10-21 02/C1, 02/L1)

tests/ZB.MOM.WW.ScadaBridge.DataConnectionLayer.Tests/Adapters/FakeMxGatewayClient.cs

@@ -24,6 +24,13 @@ public sealed class FakeMxGatewayClient : IMxGatewayClient, IMxGatewayClientFact
     public Func<IReadOnlyList<string>, IReadOnlyList<MxReadOutcome>>? ReadHandler;
     public Func<IReadOnlyList<(string TagPath, object? Value)>, IReadOnlyList<MxWriteOutcome>>? WriteHandler;
     public Func<string?, (IReadOnlyList<MxBrowseChild>, bool)>? BrowseHandler;
+    /// <summary>
+    /// When true, every <see cref="ConnectAsync"/> restarts handle numbering at 1 — the
+    /// gateway's per-session item handles, which collide across sessions.
+    /// </summary>
+    public bool RestartHandlesOnConnect;
+    /// <summary>The transition callback of the most recently opened alarm stream.</summary>
+    public Action<ZB.MOM.WW.ScadaBridge.Commons.Types.Alarms.NativeAlarmTransition>? AlarmCallback;
     private int _nextHandle;
 
     /// <inheritdoc />
@@ -33,6 +40,8 @@ public sealed class FakeMxGatewayClient : IMxGatewayClient, IMxGatewayClientFact
     public Task ConnectAsync(MxGatewayConnectionOptions o, CancellationToken ct = default)
     {
         ConnectedWith = o;
+        if (RestartHandlesOnConnect)
+            _nextHandle = 0;
         return Task.CompletedTask;
     }
 
@@ -115,6 +124,7 @@ public sealed class FakeMxGatewayClient : IMxGatewayClient, IMxGatewayClientFact
         // recorded so the union-filter (longest-common-prefix) behaviour is testable.
         lock (AlarmStreamPrefixes)
             AlarmStreamPrefixes.Add(alarmFilterPrefix);
+        AlarmCallback = onTransition;
         return Task.CompletedTask;
     }