docs: backfill XML documentation across 756 files

Adds <summary>, <param>, <typeparam>, and <inheritdoc/> tags to public
members surfaced by commentchecker — resolves 5,847 of 5,869 issues
(99.6%) across three /fixdocs passes.

tests/Client/ZB.MOM.WW.OtOpcUa.Client.CLI.Tests/SubscribeCommandTests.cs

@@ -7,6 +7,7 @@ namespace ZB.MOM.WW.OtOpcUa.Client.CLI.Tests;
 
 public class SubscribeCommandTests
 {
+    /// <summary>Verifies that ExecuteAsync subscribes with the correct parameters.</summary>
     [Fact]
     public async Task Execute_SubscribesWithCorrectParameters()
     {
@@ -35,6 +36,7 @@ public class SubscribeCommandTests
         fakeService.SubscribeCalls[0].NodeId.Identifier.ShouldBe("TestVar");
     }
 
+    /// <summary>Verifies that ExecuteAsync unsubscribes when cancellation is requested.</summary>
     [Fact]
     public async Task Execute_UnsubscribesOnCancellation()
     {
@@ -57,6 +59,7 @@ public class SubscribeCommandTests
         fakeService.UnsubscribeCalls.Count.ShouldBe(1);
     }
 
+    /// <summary>Verifies that ExecuteAsync disconnects and disposes in a finally block.</summary>
     [Fact]
     public async Task Execute_DisconnectsInFinally()
     {
@@ -80,6 +83,7 @@ public class SubscribeCommandTests
         fakeService.DisposeCalled.ShouldBeTrue();
     }
 
+    /// <summary>Verifies that ExecuteAsync prints the correct subscription message.</summary>
     [Fact]
     public async Task Execute_PrintsSubscriptionMessage()
     {