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.TwinCAT.Tests/FakeTwinCATClient.cs

@@ -5,7 +5,7 @@ namespace ZB.MOM.WW.OtOpcUa.Driver.TwinCAT.Tests;
 
 internal class FakeTwinCATClient : ITwinCATClient
 {
-    /// <summary>Gets a value indicating whether the client is connected.</summary>
+    /// <inheritdoc />
     public bool IsConnected { get; private set; }
     /// <summary>Gets the number of times Connect has been called.</summary>
     public int ConnectCount { get; private set; }
@@ -38,11 +38,7 @@ internal class FakeTwinCATClient : ITwinCATClient
     /// <summary>Test hook — fire the symbol-version-changed signal as the real client would.</summary>
     public void FireSymbolVersionChanged() => OnSymbolVersionChanged?.Invoke(this, EventArgs.Empty);
 
-    /// <summary>Simulates connecting to the TwinCAT system.</summary>
-    /// <param name="address">The AMS address to connect to.</param>
-    /// <param name="timeout">The connection timeout.</param>
-    /// <param name="ct">The cancellation token.</param>
-    /// <returns>A task that completes when the connection succeeds or fails.</returns>
+    /// <inheritdoc />
     public virtual Task ConnectAsync(TwinCATAmsAddress address, TimeSpan timeout, CancellationToken ct)
     {
         ConnectCount++;
@@ -51,12 +47,7 @@ internal class FakeTwinCATClient : ITwinCATClient
         return Task.CompletedTask;
     }
 
-    /// <summary>Simulates reading a value from a symbol.</summary>
-    /// <param name="symbolPath">The path to the symbol to read.</param>
-    /// <param name="type">The data type of the symbol.</param>
-    /// <param name="bitIndex">The optional bit index for bit-level reads.</param>
-    /// <param name="ct">The cancellation token.</param>
-    /// <returns>A task that returns the simulated value and status.</returns>
+    /// <inheritdoc />
     public virtual Task<(object? value, uint status)> ReadValueAsync(
         string symbolPath, TwinCATDataType type, int? bitIndex, CancellationToken ct)
     {
@@ -66,13 +57,7 @@ internal class FakeTwinCATClient : ITwinCATClient
         return Task.FromResult((value, status));
     }
 
-    /// <summary>Simulates writing a value to a symbol.</summary>
-    /// <param name="symbolPath">The path to the symbol to write.</param>
-    /// <param name="type">The data type of the symbol.</param>
-    /// <param name="bitIndex">The optional bit index for bit-level writes.</param>
-    /// <param name="value">The value to write.</param>
-    /// <param name="ct">The cancellation token.</param>
-    /// <returns>A task that returns the write status.</returns>
+    /// <inheritdoc />
     public virtual Task<uint> WriteValueAsync(
         string symbolPath, TwinCATDataType type, int? bitIndex, object? value, CancellationToken ct)
     {
@@ -83,9 +68,7 @@ internal class FakeTwinCATClient : ITwinCATClient
         return Task.FromResult(status);
     }
 
-    /// <summary>Simulates probing the connection status.</summary>
-    /// <param name="ct">The cancellation token.</param>
-    /// <returns>A task that returns the probe result.</returns>
+    /// <inheritdoc />
     public virtual Task<bool> ProbeAsync(CancellationToken ct)
     {
         if (ThrowOnProbe) return Task.FromResult(false);
@@ -108,15 +91,7 @@ internal class FakeTwinCATClient : ITwinCATClient
     /// <summary>Records the most recently-supplied <c>maxDelayMs</c> for Driver.TwinCAT-014 tests.</summary>
     public int LastMaxDelayMs { get; private set; }
 
-    /// <summary>Simulates adding a notification for value changes.</summary>
-    /// <param name="symbolPath">The path to the symbol to watch.</param>
-    /// <param name="type">The data type of the symbol.</param>
-    /// <param name="bitIndex">The optional bit index for bit-level notifications.</param>
-    /// <param name="cycleTime">The sampling cycle time.</param>
-    /// <param name="maxDelayMs">The maximum delay in milliseconds.</param>
-    /// <param name="onChange">The callback to invoke on value change.</param>
-    /// <param name="cancellationToken">The cancellation token.</param>
-    /// <returns>A task that returns a notification handle.</returns>
+    /// <inheritdoc />
     public virtual Task<ITwinCATNotificationHandle> AddNotificationAsync(
         string symbolPath, TwinCATDataType type, int? bitIndex, TimeSpan cycleTime,
         int maxDelayMs, Action<string, object?> onChange, CancellationToken cancellationToken)
@@ -147,9 +122,7 @@ internal class FakeTwinCATClient : ITwinCATClient
     /// <summary>Gets or sets a value indicating whether BrowseSymbolsAsync should throw.</summary>
     public bool ThrowOnBrowse { get; set; }
 
-    /// <summary>Simulates browsing the symbol tree.</summary>
-    /// <param name="cancellationToken">The cancellation token.</param>
-    /// <returns>An async enumerable of discovered symbols.</returns>
+    /// <inheritdoc />
     public virtual async IAsyncEnumerable<TwinCATDiscoveredSymbol> BrowseSymbolsAsync(
         [EnumeratorCancellation] CancellationToken cancellationToken)
     {
@@ -195,8 +168,7 @@ internal sealed class FakeTwinCATClientFactory : ITwinCATClientFactory
     /// <summary>Gets or sets an optional customization function for creating clients.</summary>
     public Func<FakeTwinCATClient>? Customise { get; set; }
 
-    /// <summary>Creates a new fake TwinCAT client.</summary>
-    /// <returns>A newly created client instance.</returns>
+    /// <inheritdoc />
     public ITwinCATClient Create()
     {
         var client = Customise?.Invoke() ?? new FakeTwinCATClient();