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.

src/Core/ZB.MOM.WW.OtOpcUa.Commons/OpcUa/DeferredAddressSpaceSink.cs

@@ -18,20 +18,41 @@ public sealed class DeferredAddressSpaceSink : IOpcUaAddressSpaceSink
 
     /// <summary>Swap in the production sink. Pass <c>null</c> to revert to the null sink
     /// (used during graceful shutdown so post-stop writes don't hit a half-disposed manager).</summary>
+    /// <param name="sink">The sink implementation to use, or null to use the null sink.</param>
     public void SetSink(IOpcUaAddressSpaceSink? sink) =>
         _inner = sink ?? NullOpcUaAddressSpaceSink.Instance;
 
+    /// <summary>Writes a value to the OPC UA address space through the inner sink.</summary>
+    /// <param name="nodeId">The node ID of the variable.</param>
+    /// <param name="value">The value to write.</param>
+    /// <param name="quality">The OPC UA quality value.</param>
+    /// <param name="sourceTimestampUtc">The source timestamp in UTC.</param>
     public void WriteValue(string nodeId, object? value, OpcUaQuality quality, DateTime sourceTimestampUtc)
         => _inner.WriteValue(nodeId, value, quality, sourceTimestampUtc);
 
+    /// <summary>Writes an alarm state through the inner sink.</summary>
+    /// <param name="alarmNodeId">The node ID of the alarm condition.</param>
+    /// <param name="active">Whether the alarm is active.</param>
+    /// <param name="acknowledged">Whether the alarm has been acknowledged.</param>
+    /// <param name="sourceTimestampUtc">The source timestamp in UTC.</param>
     public void WriteAlarmState(string alarmNodeId, bool active, bool acknowledged, DateTime sourceTimestampUtc)
         => _inner.WriteAlarmState(alarmNodeId, active, acknowledged, sourceTimestampUtc);
 
+    /// <summary>Ensures a folder exists in the address space through the inner sink.</summary>
+    /// <param name="folderNodeId">The node ID of the folder.</param>
+    /// <param name="parentNodeId">The node ID of the parent folder, or null for root.</param>
+    /// <param name="displayName">The display name of the folder.</param>
     public void EnsureFolder(string folderNodeId, string? parentNodeId, string displayName)
         => _inner.EnsureFolder(folderNodeId, parentNodeId, displayName);
 
+    /// <summary>Ensures a variable exists in the address space through the inner sink.</summary>
+    /// <param name="variableNodeId">The node ID of the variable.</param>
+    /// <param name="parentFolderNodeId">The node ID of the parent folder, or null for root.</param>
+    /// <param name="displayName">The display name of the variable.</param>
+    /// <param name="dataType">The OPC UA data type of the variable.</param>
     public void EnsureVariable(string variableNodeId, string? parentFolderNodeId, string displayName, string dataType)
         => _inner.EnsureVariable(variableNodeId, parentFolderNodeId, displayName, dataType);
 
+    /// <summary>Rebuilds the address space through the inner sink.</summary>
     public void RebuildAddressSpace() => _inner.RebuildAddressSpace();
 }