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/Client/ZB.MOM.WW.OtOpcUa.Client.Shared.Tests/Fakes/FakeSubscriptionAdapter.cs

@@ -31,8 +31,13 @@ internal sealed class FakeSubscriptionAdapter : ISubscriptionAdapter
     /// Gets or sets a value indicating whether condition refresh should throw to simulate unsupported servers.
     /// </summary>
     public bool ThrowOnConditionRefresh { get; set; }
+    /// <summary>Gets the number of times AddDataChangeMonitoredItemAsync was called.</summary>
     public int AddDataChangeCount { get; private set; }
+
+    /// <summary>Gets the number of times AddEventMonitoredItemAsync was called.</summary>
     public int AddEventCount { get; private set; }
+
+    /// <summary>Gets the number of times RemoveMonitoredItemAsync was called.</summary>
     public int RemoveCount { get; private set; }
 
     /// <summary>
@@ -115,6 +120,8 @@ internal sealed class FakeSubscriptionAdapter : ISubscriptionAdapter
     /// <summary>
     ///     Simulates a data change notification for testing.
     /// </summary>
+    /// <param name="handle">The monitored item handle.</param>
+    /// <param name="value">The new data value to simulate.</param>
     public void SimulateDataChange(uint handle, DataValue value)
     {
         (NodeId NodeId, Action<string, DataValue>? DataCallback, Action<EventFieldList>? EventCallback) item;
@@ -129,6 +136,8 @@ internal sealed class FakeSubscriptionAdapter : ISubscriptionAdapter
     /// <summary>
     ///     Simulates an event notification for testing.
     /// </summary>
+    /// <param name="handle">The monitored item handle.</param>
+    /// <param name="eventFields">The event field list to simulate.</param>
     public void SimulateEvent(uint handle, EventFieldList eventFields)
     {
         (NodeId NodeId, Action<string, DataValue>? DataCallback, Action<EventFieldList>? EventCallback) item;