docs(xmldoc): fill missing XML docs + strip tracking-ID comments across src

Adds <summary>/<param>/<returns>/<inheritdoc> where missing and removes
project bookkeeping IDs (task/tracking refs) from shipped code comments,
so the docs read cleanly and CommentChecker is quiet except for known
false positives (PLC/protocol terms, event/IEqualityComparer inheritdoc).
Doc/comment-only; no logic changed; solution builds clean.

src/Core/ZB.MOM.WW.OtOpcUa.Core.Abstractions/IAlarmSource.cs

@@ -13,6 +13,7 @@ public interface IAlarmSource
     /// </summary>
     /// <param name="sourceNodeIds">The driver node IDs to subscribe to.</param>
     /// <param name="cancellationToken">Cancellation token for the operation.</param>
+    /// <returns>A handle identifying the created subscription.</returns>
     Task<IAlarmSubscriptionHandle> SubscribeAlarmsAsync(
         IReadOnlyList<string> sourceNodeIds,
         CancellationToken cancellationToken);
@@ -20,11 +21,13 @@ public interface IAlarmSource
     /// <summary>Cancel an alarm subscription returned by <see cref="SubscribeAlarmsAsync"/>.</summary>
     /// <param name="handle">The subscription handle returned from <see cref="SubscribeAlarmsAsync"/>.</param>
     /// <param name="cancellationToken">Cancellation token for the operation.</param>
+    /// <returns>A task that represents the asynchronous operation.</returns>
     Task UnsubscribeAlarmsAsync(IAlarmSubscriptionHandle handle, CancellationToken cancellationToken);
 
     /// <summary>Acknowledge one or more active alarms by source node ID + condition ID.</summary>
     /// <param name="acknowledgements">The batch of alarm acknowledgement requests.</param>
     /// <param name="cancellationToken">Cancellation token for the operation.</param>
+    /// <returns>A task that represents the asynchronous operation.</returns>
     Task AcknowledgeAsync(
         IReadOnlyList<AlarmAcknowledgeRequest> acknowledgements,
         CancellationToken cancellationToken);