.NET client: port stream-alarms and acknowledge-alarm + fix stream-events OCE

Adds the session-less alarm CLI subcommands. stream-alarms attaches to the
gateway's central alarm feed (--filter-prefix, --max-events, --json/--jsonl);
acknowledge-alarm is a unary ack (--reference required, --comment, --operator).
StreamAlarmsAsync joins QueryActiveAlarmsAsync on MxGatewayClient and the
transport interface; the CLI client interface, adapter, and FakeGatewayTransport
follow.

Also fixes the OCE bug exposed by -VerifyWrite in the cross-language e2e:
StreamEventsAsync's await foreach now swallows OperationCanceledException when
the supplied cancellation token is the one that fired (graceful end-of-window),
and RunBatchAsync no longer excludes OCE from its outer catch — so a streaming
command that hits its --timeout reports a JSON error inside its EOR-delimited
record instead of killing the long-lived batch process.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

clients/dotnet/ZB.MOM.WW.MxGateway.Client/IMxGatewayClientTransport.cs

@@ -75,4 +75,15 @@ internal interface IMxGatewayClientTransport
     IAsyncEnumerable<ActiveAlarmSnapshot> QueryActiveAlarmsAsync(
         QueryActiveAlarmsRequest request,
         CallOptions callOptions);
+
+    /// <summary>
+    /// Attaches to the gateway's central alarm feed — the current active-alarm
+    /// snapshot followed by live transitions.
+    /// </summary>
+    /// <param name="request">The stream request, optionally scoped by alarm-reference prefix.</param>
+    /// <param name="callOptions">gRPC call options.</param>
+    /// <returns>An async enumerable of alarm feed messages.</returns>
+    IAsyncEnumerable<AlarmFeedMessage> StreamAlarmsAsync(
+        StreamAlarmsRequest request,
+        CallOptions callOptions);
 }