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.Tests/TestSupport/FakeWorkerProcess.cs

@@ -23,13 +23,13 @@ public sealed class FakeWorkerProcess(int processId) : IWorkerProcess
 {
     private readonly TaskCompletionSource _exited = new(TaskCreationOptions.RunContinuationsAsynchronously);
 
-    /// <summary>Gets the process identifier.</summary>
+    /// <inheritdoc />
     public int Id { get; } = processId;
 
-    /// <summary>Gets or sets a value indicating whether the process has exited.</summary>
+    /// <inheritdoc />
     public bool HasExited { get; set; }
 
-    /// <summary>Gets or sets the exit code of the process, or <see langword="null"/> if it has not exited.</summary>
+    /// <inheritdoc />
     public int? ExitCode { get; set; }
 
     /// <summary>Gets the number of times <see cref="Kill"/> was called.</summary>
@@ -62,7 +62,7 @@ public sealed class FakeWorkerProcess(int processId) : IWorkerProcess
         MarkExited(-1);
     }
 
-    /// <inheritdoc />
+    /// <summary>Marks this fake as disposed so tests can assert <see cref="Dispose"/> was called.</summary>
     public void Dispose() => IsDisposed = true;
 
     /// <summary>

src/ZB.MOM.WW.MxGateway.Tests/TestSupport/NullDashboardEventBroadcaster.cs

@@ -7,7 +7,7 @@ namespace ZB.MOM.WW.MxGateway.Tests.TestSupport;
 /// <see cref="IDashboardEventBroadcaster"/> that drops every event on the floor.
 /// Used by tests that need to wire up <c>EventStreamService</c> but do not care
 /// about the dashboard fan-out side-channel. The singleton <see cref="Instance"/>
-/// mirrors the Tests-007 / Tests-021 shared-fake pattern under
+/// mirrors the shared-fake pattern under
 /// <c>src/ZB.MOM.WW.MxGateway.Tests/TestSupport/</c>.
 /// </summary>
 public sealed class NullDashboardEventBroadcaster : IDashboardEventBroadcaster

src/ZB.MOM.WW.MxGateway.Tests/TestSupport/RecordingDashboardEventBroadcaster.cs

@@ -8,7 +8,7 @@ namespace ZB.MOM.WW.MxGateway.Tests.TestSupport;
 /// <see cref="IDashboardEventBroadcaster"/> test double that captures every
 /// <c>Publish(sessionId, mxEvent)</c> call into a thread-safe list, so tests
 /// can prove the gRPC producer loop actually mirrors events to the dashboard
-/// fan-out seam. Tests-026.
+/// fan-out seam.
 /// </summary>
 public sealed class RecordingDashboardEventBroadcaster : IDashboardEventBroadcaster
 {