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/InputValidationErrorsTests.cs

@@ -13,6 +13,7 @@ namespace ZB.MOM.WW.OtOpcUa.Client.CLI.Tests;
 /// </summary>
 public class InputValidationErrorsTests
 {
+    /// <summary>Verifies that HistoryReadCommand with invalid start time throws CommandException.</summary>
     [Fact]
     public async Task HistoryReadCommand_InvalidStartTime_ThrowsCommandException()
     {
@@ -30,6 +31,7 @@ public class InputValidationErrorsTests
         ex.Message.ShouldContain("--start");
     }
 
+    /// <summary>Verifies that HistoryReadCommand with invalid end time throws CommandException.</summary>
     [Fact]
     public async Task HistoryReadCommand_InvalidEndTime_ThrowsCommandException()
     {
@@ -47,6 +49,7 @@ public class InputValidationErrorsTests
         ex.Message.ShouldContain("--end");
     }
 
+    /// <summary>Verifies that HistoryReadCommand with invalid aggregate throws CommandException.</summary>
     [Fact]
     public async Task HistoryReadCommand_InvalidAggregate_ThrowsCommandException()
     {
@@ -64,6 +67,7 @@ public class InputValidationErrorsTests
         ex.Message.ShouldContain("aggregate", Case.Insensitive);
     }
 
+    /// <summary>Verifies that ReadCommand with invalid node ID throws CommandException.</summary>
     [Fact]
     public async Task ReadCommand_InvalidNodeId_ThrowsCommandException()
     {
@@ -80,6 +84,7 @@ public class InputValidationErrorsTests
         ex.Message.ShouldContain("node", Case.Insensitive);
     }
 
+    /// <summary>Verifies that SubscribeCommand with invalid node ID throws CommandException.</summary>
     [Fact]
     public async Task SubscribeCommand_InvalidNodeId_ThrowsCommandException()
     {