docs: complete XML doc coverage (returns, summaries, inheritdoc)

Resolve all 622 issues flagged by the enhanced CommentChecker: add missing
<returns> tags (incl. the standard phrasing on non-generic Task methods),
add missing <summary> tags, and replace misused/redundant <inheritdoc/> on
members that override or implement nothing with real documentation.
Documentation-only — no behavior change; solution builds clean.

src/ZB.MOM.WW.ScadaBridge.Commons/Messages/Management/ManagementCommandRegistry.cs

@@ -29,6 +29,7 @@ public static class ManagementCommandRegistry
     /// Resolves a management command wire name to its CLR type, or null if not registered.
     /// </summary>
     /// <param name="commandName">The wire name of the management command (without the "Command" suffix).</param>
+    /// <returns>The CLR <see cref="Type"/> for the command, or <c>null</c> if not registered.</returns>
     public static Type? Resolve(string commandName)
     {
         return Commands.GetValueOrDefault(commandName);
@@ -45,6 +46,7 @@ public static class ManagementCommandRegistry
     /// symmetric with <see cref="Resolve"/>: it never yields a name that
     /// <see cref="Resolve"/> cannot turn back into the same type.
     /// </exception>
+    /// <returns>The registered wire name for <paramref name="commandType"/>.</returns>
     public static string GetCommandName(Type commandType)
     {
         ArgumentNullException.ThrowIfNull(commandType);