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/Drivers/ZB.MOM.WW.OtOpcUa.Driver.OpcUaClient.Tests/OpcUaClientDiscoveryTests.cs

@@ -13,6 +13,7 @@ namespace ZB.MOM.WW.OtOpcUa.Driver.OpcUaClient.Tests;
 public sealed class OpcUaClientDiscoveryTests
 {
     /// <summary>Verifies that DiscoverAsync throws InvalidOperationException when not initialized.</summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
     [Fact]
     public async Task DiscoverAsync_without_initialize_throws_InvalidOperationException()
     {
@@ -44,22 +45,14 @@ public sealed class OpcUaClientDiscoveryTests
     /// <summary>Test builder that provides no-op implementations for discovery tests.</summary>
     private sealed class NullAddressSpaceBuilder : IAddressSpaceBuilder
     {
-        /// <summary>Returns this builder (no-op).</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) => this;
 
-        /// <summary>Returns a stub handle.</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 for the variable.</param>
+        /// <inheritdoc />
         public IVariableHandle Variable(string browseName, string displayName, DriverAttributeInfo attributeInfo)
             => new StubHandle();
 
-        /// <summary>No-op 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) { }
 
         /// <summary>No-op alarm condition attachment.</summary>
@@ -71,11 +64,10 @@ public sealed class OpcUaClientDiscoveryTests
         /// <summary>Stub variable handle for testing.</summary>
         private sealed class StubHandle : IVariableHandle
         {
-            /// <summary>Gets the full reference as "stub".</summary>
+            /// <inheritdoc />
             public string FullReference => "stub";
 
-            /// <summary>Throws NotSupportedException.</summary>
-            /// <param name="info">The alarm condition information (unused).</param>
+            /// <inheritdoc />
             public IAlarmConditionSink MarkAsAlarmCondition(AlarmConditionInfo info) => throw new NotSupportedException();
         }
     }