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.OpcUaClient.Tests/OpcUaClientAttributeMappingTests.cs

@@ -8,6 +8,9 @@ namespace ZB.MOM.WW.OtOpcUa.Driver.OpcUaClient.Tests;
 [Trait("Category", "Unit")]
 public sealed class OpcUaClientAttributeMappingTests
 {
+    /// <summary>Verifies that MapUpstreamDataType recognizes standard builtin OPC UA types.</summary>
+    /// <param name="typeId">The OPC UA data type ID.</param>
+    /// <param name="expected">The expected driver data type.</param>
     [Theory]
     [InlineData((uint)DataTypes.Boolean, DriverDataType.Boolean)]
     [InlineData((uint)DataTypes.SByte, DriverDataType.Int16)]
@@ -28,6 +31,7 @@ public sealed class OpcUaClientAttributeMappingTests
         OpcUaClientDriver.MapUpstreamDataType(nodeId).ShouldBe(expected);
     }
 
+    /// <summary>Verifies that MapUpstreamDataType maps SByte to Int16 since DriverDataType lacks 8-bit signed.</summary>
     [Fact]
     public void MapUpstreamDataType_maps_SByte_to_Int16_since_DriverDataType_lacks_8bit_signed()
     {
@@ -35,6 +39,7 @@ public sealed class OpcUaClientAttributeMappingTests
         OpcUaClientDriver.MapUpstreamDataType(new NodeId((uint)DataTypes.SByte)).ShouldBe(DriverDataType.Int16);
     }
 
+    /// <summary>Verifies that MapUpstreamDataType maps Byte to UInt16 not Int16.</summary>
     [Fact]
     public void MapUpstreamDataType_maps_Byte_to_UInt16_not_Int16()
     {
@@ -44,6 +49,7 @@ public sealed class OpcUaClientAttributeMappingTests
         OpcUaClientDriver.MapUpstreamDataType(new NodeId((uint)DataTypes.Byte)).ShouldBe(DriverDataType.UInt16);
     }
 
+    /// <summary>Verifies that MapUpstreamDataType falls back to String for unknown custom types.</summary>
     [Fact]
     public void MapUpstreamDataType_falls_back_to_String_for_unknown_custom_types()
     {
@@ -51,12 +57,16 @@ public sealed class OpcUaClientAttributeMappingTests
         OpcUaClientDriver.MapUpstreamDataType(new NodeId("CustomStruct", 2)).ShouldBe(DriverDataType.String);
     }
 
+    /// <summary>Verifies that MapUpstreamDataType handles UtcTime as DateTime.</summary>
     [Fact]
     public void MapUpstreamDataType_handles_UtcTime_as_DateTime()
     {
         OpcUaClientDriver.MapUpstreamDataType(new NodeId((uint)DataTypes.UtcTime)).ShouldBe(DriverDataType.DateTime);
     }
 
+    /// <summary>Verifies that MapAccessLevelToSecurityClass respects the CurrentWrite bit.</summary>
+    /// <param name="accessLevel">The access level byte.</param>
+    /// <param name="expected">The expected security classification.</param>
     [Theory]
     [InlineData((byte)0, SecurityClassification.ViewOnly)]           // no access flags set
     [InlineData((byte)1, SecurityClassification.ViewOnly)]           // CurrentRead only