feat(client-cli): add ack/confirm/shelve alarm commands with service layer

Adds ConfirmAlarmAsync and ShelveAlarmAsync to IOpcUaClientService and
OpcUaClientService (mirroring the AcknowledgeAlarmAsync pattern: same
CallMethodAsync/ServiceResultException/StatusCode contract). Adds ShelveKind
enum (OneShot/Timed/Unshelve). Adds three new CLI commands — ack, confirm,
shelve — with hex EventId input and per-command argument validation.
Updates both fakes (CLI + UI) to implement the new interface members and
record calls. Adds 16 unit tests covering argument mapping, invalid-input
CommandException paths, bad-status output, and disconnect-in-finally.

src/Client/ZB.MOM.WW.OtOpcUa.Client.Shared/IOpcUaClientService.cs

@@ -103,6 +103,36 @@ public interface IOpcUaClientService : IDisposable
     /// </returns>
     Task<StatusCode> AcknowledgeAlarmAsync(string conditionNodeId, byte[] eventId, string comment, CancellationToken ct = default);
 
+    /// <summary>
+    /// Confirms an acknowledged condition (Part 9 two-stage acknowledgment) using the event identifier returned by an alarm notification.
+    /// </summary>
+    /// <param name="conditionNodeId">The condition node associated with the alarm event being confirmed.</param>
+    /// <param name="eventId">The event identifier returned by the OPC UA server for the alarm event.</param>
+    /// <param name="comment">The operator confirmation comment to write with the method call.</param>
+    /// <param name="ct">The cancellation token that aborts the confirmation request.</param>
+    /// <returns>
+    /// <see cref="StatusCodes.Good"/> on success, or the server's bad <see cref="StatusCode"/>
+    /// (from the underlying <see cref="ServiceResultException"/>) when the confirm call
+    /// returns a bad result. Other transport-level failures still surface as exceptions.
+    /// </returns>
+    Task<StatusCode> ConfirmAlarmAsync(string conditionNodeId, byte[] eventId, string comment, CancellationToken ct = default);
+
+    /// <summary>
+    /// Shelves or unshelves an active alarm condition (OPC UA Part 9 ShelvedStateMachine).
+    /// </summary>
+    /// <param name="conditionNodeId">The condition node associated with the alarm being shelved.</param>
+    /// <param name="kind">The shelve operation: <c>OneShot</c>, <c>Timed</c>, or <c>Unshelve</c>.</param>
+    /// <param name="shelvingTimeSeconds">
+    /// For <c>Timed</c> shelving: the shelving duration in seconds. Ignored for <c>OneShot</c> and <c>Unshelve</c>.
+    /// </param>
+    /// <param name="ct">The cancellation token that aborts the shelve request.</param>
+    /// <returns>
+    /// <see cref="StatusCodes.Good"/> on success, or the server's bad <see cref="StatusCode"/>
+    /// (from the underlying <see cref="ServiceResultException"/>) when the shelve call
+    /// returns a bad result. Other transport-level failures still surface as exceptions.
+    /// </returns>
+    Task<StatusCode> ShelveAlarmAsync(string conditionNodeId, ShelveKind kind, double shelvingTimeSeconds = 0, CancellationToken ct = default);
+
     /// <summary>
     /// Reads raw historical samples for a historized node.
     /// </summary>