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/Security/Authorization/IConstraintEnforcer.cs

@@ -9,6 +9,7 @@ public interface IConstraintEnforcer
     /// <param name="identity">The API key identity.</param>
     /// <param name="tagAddress">Tag address to check.</param>
     /// <param name="cancellationToken">Token to observe for cancellation.</param>
+    /// <returns>The constraint failure details if denied; otherwise null.</returns>
     Task<ConstraintFailure?> CheckReadTagAsync(
         ApiKeyIdentity? identity,
         string tagAddress,
@@ -20,6 +21,7 @@ public interface IConstraintEnforcer
     /// <param name="serverHandle">The MXAccess server handle.</param>
     /// <param name="itemHandle">The MXAccess item handle.</param>
     /// <param name="cancellationToken">Token to observe for cancellation.</param>
+    /// <returns>The constraint failure details if denied; otherwise null.</returns>
     Task<ConstraintFailure?> CheckReadHandleAsync(
         ApiKeyIdentity? identity,
         GatewaySession session,
@@ -33,6 +35,7 @@ public interface IConstraintEnforcer
     /// <param name="serverHandle">The MXAccess server handle.</param>
     /// <param name="itemHandle">The MXAccess item handle.</param>
     /// <param name="cancellationToken">Token to observe for cancellation.</param>
+    /// <returns>The constraint failure details if denied; otherwise null.</returns>
     Task<ConstraintFailure?> CheckWriteHandleAsync(
         ApiKeyIdentity? identity,
         GatewaySession session,
@@ -50,6 +53,7 @@ public interface IConstraintEnforcer
     ///     <c>CorrelationId</c> when it parses as a GUID; otherwise left null.
     /// </param>
     /// <param name="cancellationToken">Token to observe for cancellation.</param>
+    /// <returns>A task that represents the asynchronous operation.</returns>
     Task RecordDenialAsync(
         ApiKeyIdentity? identity,
         string commandKind,