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/Drivers/ZB.MOM.WW.OtOpcUa.Driver.AbCip.Tests/AbCipUdtMemberLayoutTests.cs

@@ -6,6 +6,7 @@ namespace ZB.MOM.WW.OtOpcUa.Driver.AbCip.Tests;
 [Trait("Category", "Unit")]
 public sealed class AbCipUdtMemberLayoutTests
 {
+    /// <summary>Verifies that packed atomic types get natural alignment offsets.</summary>
     [Fact]
     public void Packed_Atomics_Get_Natural_Alignment_Offsets()
     {
@@ -27,6 +28,7 @@ public sealed class AbCipUdtMemberLayoutTests
         offsets["D"].ShouldBe(16);
     }
 
+    /// <summary>Verifies that signed integer types are packed without padding.</summary>
     [Fact]
     public void SInt_Packed_Without_Padding()
     {
@@ -42,6 +44,7 @@ public sealed class AbCipUdtMemberLayoutTests
         offsets["Z"].ShouldBe(2);
     }
 
+    /// <summary>Verifies that layout returns null when a member is a Bool type.</summary>
     [Fact]
     public void Returns_Null_When_Member_Is_Bool()
     {
@@ -55,6 +58,7 @@ public sealed class AbCipUdtMemberLayoutTests
         AbCipUdtMemberLayout.TryBuild(members).ShouldBeNull();
     }
 
+    /// <summary>Verifies that layout returns null when a member is a String or Structure type.</summary>
     [Fact]
     public void Returns_Null_When_Member_Is_String_Or_Structure()
     {
@@ -64,6 +68,7 @@ public sealed class AbCipUdtMemberLayoutTests
             new[] { new AbCipStructureMember("Nested", AbCipDataType.Structure) }).ShouldBeNull();
     }
 
+    /// <summary>Verifies that layout returns null when the member list is empty.</summary>
     [Fact]
     public void Returns_Null_On_Empty_Members()
     {