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/Client/ZB.MOM.WW.OtOpcUa.Client.Shared/Adapters/IEndpointDiscovery.cs

@@ -14,6 +14,7 @@ internal interface IEndpointDiscovery
     /// <param name="config">The OPC UA application configuration.</param>
     /// <param name="endpointUrl">The endpoint URL to discover.</param>
     /// <param name="requestedMode">The requested message security mode.</param>
+    /// <returns>The best-matching endpoint description, with its URL hostname rewritten to match <paramref name="endpointUrl"/> when they differ.</returns>
     EndpointDescription SelectEndpoint(ApplicationConfiguration config, string endpointUrl,
         MessageSecurityMode requestedMode);
 }