docs+ui: backfill XML doc comments and finish dashboard layout pass

Adds missing <summary>/<param> XML docs across 99 server, worker, and test
files so CommentChecker reports zero issues (TreatWarningsAsErrors needs the
analyzer clean). Bundles in WIP dashboard work: NavSection extraction,
MainLayout/site.css/js styling alignment, and DashboardOptions/Auth tweaks.

src/ZB.MOM.WW.MxGateway.Tests/Gateway/Workers/WorkerClientTests.cs

@@ -247,6 +247,7 @@ public sealed class WorkerClientTests
         Assert.Equal(WorkerClientState.Faulted, client.State);
     }
 
+    /// <summary>Verifies that pipe disconnect faults the client.</summary>
     [Fact]
     public async Task ReadLoop_WhenPipeDisconnects_FaultsClient()
     {
@@ -767,23 +768,32 @@ public sealed class WorkerClientTests
     {
         private readonly TaskCompletionSource _exited = new(TaskCreationOptions.RunContinuationsAsynchronously);
 
+        /// <summary>Gets the process ID.</summary>
         public int Id { get; } = WorkerProcessId;
 
+        /// <summary>Gets a value indicating whether the process has exited.</summary>
         public bool HasExited { get; private set; }
 
+        /// <summary>Gets the process exit code.</summary>
         public int? ExitCode { get; private set; }
 
+        /// <summary>Gets the number of times kill was called.</summary>
         public int KillCount { get; private set; }
 
+        /// <summary>Gets the last kill request's entire process tree flag.</summary>
         public bool KillEntireProcessTree { get; private set; }
 
+        /// <summary>Gets a value indicating whether dispose was called.</summary>
         public bool Disposed { get; private set; }
 
+        /// <inheritdoc />
         public ValueTask WaitForExitAsync(CancellationToken cancellationToken)
         {
             return new ValueTask(_exited.Task.WaitAsync(cancellationToken));
         }
 
+        /// <summary>Records a kill request.</summary>
+        /// <param name="entireProcessTree">Whether to kill the entire process tree.</param>
         public void Kill(bool entireProcessTree)
         {
             KillCount++;
@@ -793,6 +803,7 @@ public sealed class WorkerClientTests
             _exited.TrySetResult();
         }
 
+        /// <inheritdoc />
         public void Dispose()
         {
             Disposed = true;