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/Sessions/SessionEventStreaming.cs

@@ -15,7 +15,7 @@ namespace ZB.MOM.WW.MxGateway.Server.Sessions;
 /// <param name="Mapper">
 ///     Maps worker IPC <c>WorkerEvent</c> frames to public <c>MxEvent</c>s. The distributor
 ///     pump applies this once per event in worker order, mirroring the mapping
-///     <c>EventStreamService.ProduceEventsAsync</c> used before Task 4.
+///     <c>EventStreamService.ProduceEventsAsync</c> used previously.
 /// </param>
 /// <param name="EventOptions">
 ///     Supplies the distributor's per-subscriber queue capacity and replay ring-buffer
@@ -32,20 +32,20 @@ namespace ZB.MOM.WW.MxGateway.Server.Sessions;
 ///     preserving the observability the pre-epic per-RPC overflow path emitted.
 /// </param>
 /// <param name="DashboardBroadcaster">
-///     Sink the session's internal dashboard mirror loop (Task 6) publishes raw session
+///     Sink the session's internal dashboard mirror loop publishes raw session
 ///     <c>MxEvent</c>s to. When non-null the session registers an internal distributor
 ///     subscriber on becoming Ready and mirrors every fanned event to the dashboard
 ///     EventsHub group regardless of whether a gRPC client is streaming. When null
 ///     (unit tests that don't exercise the dashboard mirror) no mirror is started.
 /// </param>
 /// <param name="AllowMultipleEventSubscribers">
-///     The session's effective multi-subscriber mode (Task 8). Carried here so the session
+///     The session's effective multi-subscriber mode. Carried here so the session
 ///     can pass it to its <see cref="SessionEventDistributor"/> at construction — the
 ///     distributor is created at <c>MarkReady</c> (for the dashboard mirror) before any gRPC
 ///     subscriber attaches, so the mode cannot be learned from a later
 ///     <c>AttachEventSubscriber</c> call. The distributor gates its FailFast session-fault
 ///     decision on this mode (single-subscriber only) instead of a live count snapshot,
-///     closing the Task 5 false-FailFast race. Defaults to <see langword="false"/>
+///     closing the false-FailFast race. Defaults to <see langword="false"/>
 ///     (single-subscriber) so existing call sites and unit tests are unchanged.
 /// </param>
 public sealed record SessionEventStreaming(