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/Configuration/WorkerOptions.cs

@@ -37,8 +37,8 @@ public sealed class WorkerOptions
     /// The maximum worker-frame (pipe) message size in bytes. Must stay at least
     /// <see cref="Workers.WorkerFrameProtocolOptions.EnvelopeOverheadReserveBytes"/> above
     /// <see cref="ProtocolOptions.MaxGrpcMessageBytes"/> so a maximally-sized accepted gRPC payload
-    /// still fits one worker frame (IPC-03); the gateway conveys this value to the worker in the
-    /// handshake (<c>GatewayHello.max_frame_bytes</c>, IPC-02). Default is the 16 MB public gRPC cap
+    /// still fits one worker frame; the gateway conveys this value to the worker in the
+    /// handshake (<c>GatewayHello.max_frame_bytes</c>). Default is the 16 MB public gRPC cap
     /// plus that reserve.
     /// </summary>
     public int MaxMessageBytes { get; init; } =