docs: complete XML-doc coverage and strip internal tracking IDs from code comments

Resolve all CommentChecker findings across the gateway server, worker, tests,
and .NET client (314 -> 0 real issues): add missing <returns>/<summary>/<param>
on public and test members, convert Stream/interface overrides to <inheritdoc/>,
and remove internal task/issue tracking IDs (SEC-*, IPC-*, WRK-*, GWC-*, TST-*,
Client.Dotnet-*) from shipped code documentation while preserving the design
rationale prose. Shipped comments should not carry internal bookkeeping, and
complete XML docs keep the analyzer/TreatWarningsAsErrors gate and generated API
docs clean. The 6 remaining flags are heuristic false positives (MD5, UTC-4,
capacity-1, near-1601) left intact so real documentation is not corrupted.

Claude-Session: https://claude.ai/code/session_01DMXXvNuPekkkrTEyPNxEkW

src/ZB.MOM.WW.MxGateway.Server/Workers/WorkerClient.cs

@@ -27,7 +27,7 @@ public sealed class WorkerClient : IWorkerClient
 
     // Staging hand-off between the read loop and the dedicated event writer. The read loop writes
     // here with a non-blocking TryWrite so a full consumer channel (_events) can never stall the read
-    // loop behind an event — replies and heartbeats keep flowing (GWC-04). Unbounded, but only fills
+    // loop behind an event — replies and heartbeats keep flowing. Unbounded, but only fills
     // during the bounded EventChannelFullModeTimeout window before EventWriteLoopAsync faults on a
     // sustained backlog, after which the read loop stops.
     private readonly Channel<WorkerEvent> _eventStaging;
@@ -208,7 +208,7 @@ public sealed class WorkerClient : IWorkerClient
 
             // Reject an oversized command at the enqueue boundary so only this correlation fails
             // (ResourceExhausted) rather than the frame reaching the write loop and faulting the whole
-            // session (IPC-03). Command envelopes are the only gateway-authored outbound payload whose
+            // session. Command envelopes are the only gateway-authored outbound payload whose
             // size the caller controls; checking here keeps a MessageTooLarge in the write loop a
             // genuine desync signal.
             int envelopeSize = commandEnvelope.CalculateSize();
@@ -269,7 +269,7 @@ public sealed class WorkerClient : IWorkerClient
         // The event channel is SingleReader: only one enumerator may ever drain it, otherwise
         // the two readers would each receive a random subset of events. Claim the reader at CALL
         // time (not lazily on first MoveNext) and fail loudly on a second consumer rather than
-        // silently splitting the stream (see GWC-01). The distributor pump is the only intended
+        // silently splitting the stream. The distributor pump is the only intended
         // caller; the alarm monitor and dashboard mirror attach to the distributor instead.
         if (Interlocked.CompareExchange(ref _eventsReaderClaimed, 1, 0) != 0)
         {
@@ -519,7 +519,7 @@ public sealed class WorkerClient : IWorkerClient
     ///     Routes a received envelope to its handler. Every branch dispatches synchronously and
     ///     immediately — the event branch only stages the event for the dedicated writer — so a full
     ///     event channel can never delay a command reply, heartbeat, fault, or shutdown ack behind an
-    ///     event backlog (GWC-04).
+    ///     event backlog.
     /// </summary>
     /// <param name="envelope">The envelope to dispatch.</param>
     private void DispatchEnvelope(WorkerEnvelope envelope)
@@ -559,7 +559,7 @@ public sealed class WorkerClient : IWorkerClient
     ///     succeeds unless the channel has been completed during shutdown — in which case the event is
     ///     safely dropped because the client is closing. Backpressure and the sustained-overflow fault
     ///     are applied by <see cref="EventWriteLoopAsync"/> against the bounded consumer channel,
-    ///     off the read loop (GWC-04).
+    ///     off the read loop.
     /// </summary>
     /// <param name="workerEvent">The event received from the worker.</param>
     private void StageWorkerEvent(WorkerEvent workerEvent)
@@ -575,7 +575,7 @@ public sealed class WorkerClient : IWorkerClient
     /// <summary>
     ///     Drains staged worker events and applies the bounded-channel backpressure (and
     ///     sustained-overflow fault) on a dedicated task, so the timed <see cref="Channel"/> write
-    ///     never runs on the read loop (GWC-04). Mirrors <see cref="WriteLoopAsync"/> for events.
+    ///     never runs on the read loop. Mirrors <see cref="WriteLoopAsync"/> for events.
     /// </summary>
     private async Task EventWriteLoopAsync()
     {
@@ -984,7 +984,7 @@ public sealed class WorkerClient : IWorkerClient
                 GatewayVersion = typeof(GatewayContractInfo).Assembly.GetName().Version?.ToString() ?? GatewayVersionFallback,
 
                 // Convey the negotiated worker-frame maximum so the worker adopts it instead of a
-                // hard-coded default (IPC-02). Sits above the public gRPC cap by the envelope reserve.
+                // hard-coded default. Sits above the public gRPC cap by the envelope reserve.
                 MaxFrameBytes = (uint)_connection.FrameOptions.MaxMessageBytes,
             });
     }

src/ZB.MOM.WW.MxGateway.Server/Workers/WorkerClientErrorCode.cs

@@ -15,6 +15,6 @@ public enum WorkerClientErrorCode
 
     // The serialized command envelope exceeds the negotiated worker-frame maximum. Rejected at the
     // enqueue boundary so only the offending command fails (mapped to ResourceExhausted) instead of
-    // the oversized frame reaching the write loop and faulting the whole session (IPC-03).
+    // the oversized frame reaching the write loop and faulting the whole session.
     CommandTooLarge,
 }

src/ZB.MOM.WW.MxGateway.Server/Workers/WorkerFrameProtocolOptions.cs

@@ -15,7 +15,7 @@ public sealed class WorkerFrameProtocolOptions
     /// gRPC payload accepted at the public boundary always fits inside one worker frame once wrapped
     /// in a <c>WorkerEnvelope</c> (correlation id, timestamps, oneof framing). Without this headroom
     /// the pipe max equals the gRPC max and a maximally-sized accepted request faults the whole
-    /// session on the outbound write (IPC-03). 64 KiB is far larger than the fixed envelope overhead.
+    /// session on the outbound write. 64 KiB is far larger than the fixed envelope overhead.
     /// </summary>
     public const int EnvelopeOverheadReserveBytes = 64 * 1024;