docs(src): add missing XML docs and strip tracking-ID comments

Sweep of 203 source files resolving CommentChecker findings: add
<summary>/<param>/<returns>/<inheritdoc> where missing, and remove
resolved task/issue tracking markers (Tests-NNN, Worker-NNN, Server-NNN,
Task N) from code comments. Comment/doc-only — no logic changes.
Server+Tests build clean under TreatWarningsAsErrors.

src/ZB.MOM.WW.MxGateway.Server/Alarms/GatewayAlarmMonitor.cs

@@ -912,6 +912,7 @@ public sealed class GatewayAlarmMonitor : BackgroundService, IGatewayAlarmServic
 
         /// <summary>Determines whether the alarm reference matches this subscriber's filter.</summary>
         /// <param name="reference">The alarm reference to match.</param>
+        /// <returns><see langword="true"/> if the reference matches this subscriber's prefix filter.</returns>
         public bool Matches(string reference)
         {
             return prefix.Length == 0 || reference.StartsWith(prefix, StringComparison.Ordinal);