docs: complete XML doc comments via fixdocs (2757 to 131 findings)

Add missing <returns>/<param>/<summary>/<typeparam> tags and clean up
misused inheritdoc across 481 files so the documented API surface is
complete. Documentation-only (zero code lines changed). The 131 remaining
findings are inheritdoc-style warnings deliberately left to preserve
hand-written implementation rationale (plan-decision notes, race-condition
explanations).

tests/Core/ZB.MOM.WW.OtOpcUa.Core.Tests/OpcUa/IdentificationFolderBuilderTests.cs

@@ -18,26 +18,18 @@ public sealed class IdentificationFolderBuilderTests
         /// <summary>Gets or sets the list of added properties.</summary>
         public List<(string BrowseName, DriverDataType DataType, object? Value)> Properties { get; } = [];
 
-        /// <summary>Records a folder and returns this builder for chaining.</summary>
-        /// <param name="browseName">The browse name of the folder.</param>
-        /// <param name="displayName">The display name of the folder.</param>
+        /// <inheritdoc />
         public IAddressSpaceBuilder Folder(string browseName, string displayName)
         {
             Folders.Add((browseName, displayName));
             return this; // flat recording — identification fields land in the same bucket
         }
 
-        /// <summary>Not supported in test context.</summary>
-        /// <param name="browseName">The browse name of the variable.</param>
-        /// <param name="displayName">The display name of the variable.</param>
-        /// <param name="attributeInfo">The attribute information.</param>
+        /// <inheritdoc />
         public IVariableHandle Variable(string browseName, string displayName, DriverAttributeInfo attributeInfo)
             => throw new NotSupportedException("Identification fields use AddProperty, not Variable");
 
-        /// <summary>Records a property addition.</summary>
-        /// <param name="browseName">The browse name of the property.</param>
-        /// <param name="dataType">The data type of the property.</param>
-        /// <param name="value">The property value.</param>
+        /// <inheritdoc />
         public void AddProperty(string browseName, DriverDataType dataType, object? value)
             => Properties.Add((browseName, dataType, value));
     }