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/Workers/WorkerServiceCollectionExtensions.cs

@@ -5,6 +5,7 @@ public static class WorkerServiceCollectionExtensions
 {
     /// <summary>Registers worker process launcher and factory services.</summary>
     /// <param name="services">Service collection to register services.</param>
+    /// <returns>The same service collection, for chaining.</returns>
     public static IServiceCollection AddWorkerProcessLauncher(this IServiceCollection services)
     {
         services.AddSingleton<IWorkerProcessFactory, SystemWorkerProcessFactory>();