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/Drivers/ZB.MOM.WW.OtOpcUa.Driver.FOCAS/Wire/FocasConstants.cs

@@ -57,12 +57,14 @@ public enum FocasOperationMode : short
 public static class FocasOperationModeExtensions
 {
     /// <summary>
-    ///     Canonical operator-facing label for an operation mode (e.g. <c>"AUTO"</c>,
+    ///     Gets the canonical operator-facing label for an operation mode (e.g. <c>"AUTO"</c>,
     ///     <c>"EDIT"</c>). Delegates to <see cref="FocasOpMode.ToText"/> so the wire layer
     ///     and the fixed-tree projection render identical labels — historically these two
     ///     surfaces diverged ("TJOG" vs "T-JOG", "TEACH_IN_HANDLE" vs "TEACH-IN-HANDLE",
     ///     and different unknown-code fallbacks). Resolved by Driver.FOCAS-010.
     /// </summary>
+    /// <param name="mode">The operation mode.</param>
+    /// <returns>The operator-facing label.</returns>
     public static string ToText(this FocasOperationMode mode) =>
         FocasOpMode.ToText((short)mode);
 }
@@ -74,6 +76,9 @@ public static class FocasOperationModeExtensions
 /// </summary>
 internal static class FocasPmcAreaLookup
 {
+    /// <summary>Looks up a PMC area code by letter.</summary>
+    /// <param name="letter">The PMC area letter (case-insensitive).</param>
+    /// <returns>The corresponding FocasPmcArea, or null if not recognized.</returns>
     public static FocasPmcArea? FromLetter(string letter) => letter.ToUpperInvariant() switch
     {
         "G" => FocasPmcArea.G,
@@ -98,6 +103,9 @@ internal static class FocasPmcAreaLookup
 /// </summary>
 internal static class FocasPmcDataTypeLookup
 {
+    /// <summary>Maps a FocasDataType to the corresponding PMC wire data type.</summary>
+    /// <param name="t">The FOCAS data type.</param>
+    /// <returns>The PMC data type for wire communication.</returns>
     public static FocasPmcDataType FromFocasDataType(FocasDataType t) => t switch
     {
         FocasDataType.Bit or FocasDataType.Byte => FocasPmcDataType.Byte,