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/Client/ZB.MOM.WW.OtOpcUa.Client.UI/Program.cs

@@ -4,8 +4,11 @@ using ZB.MOM.WW.OtOpcUa.Client.Shared;
 
 namespace ZB.MOM.WW.OtOpcUa.Client.UI;
 
+/// <summary>Entry point for the OPC UA client UI application.</summary>
 public class Program
 {
+    /// <summary>Main entry point for the application.</summary>
+    /// <param name="args">Command-line arguments passed to the application.</param>
     [STAThread]
     public static void Main(string[] args)
     {
@@ -21,6 +24,8 @@ public class Program
         }
     }
 
+    /// <summary>Builds the Avalonia AppBuilder with platform-specific configuration.</summary>
+    /// <returns>Configured AppBuilder for desktop lifetime.</returns>
     public static AppBuilder BuildAvaloniaApp()
     {
         return AppBuilder.Configure<App>()