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.Host/LoggerConfigurationFactory.cs

@@ -52,6 +52,7 @@ public static class LoggerConfigurationFactory
     /// <param name="siteId">Site identifier added as a log enrichment property.</param>
     /// <param name="nodeHostname">Hostname added as a log enrichment property.</param>
     /// <param name="warningWriter">Writer that receives the one-shot Host-020 override-warning when both keys are present.</param>
+    /// <returns>The fully configured <see cref="LoggerConfiguration"/> ready to create the Serilog logger.</returns>
     internal static LoggerConfiguration Build(
         IConfiguration configuration,
         string nodeRole,
@@ -104,6 +105,8 @@ public static class LoggerConfigurationFactory
     /// Null/blank values are treated as "unset" and silently default — only
     /// explicit-but-invalid values trigger the warning.
     /// </summary>
+    /// <param name="level">Configured level string, possibly null/blank/invalid.</param>
+    /// <returns>The parsed <see cref="LogEventLevel"/>, or <see cref="LogEventLevel.Information"/> when the value is absent or unrecognised.</returns>
     internal static LogEventLevel ParseLevel(string? level)
         => ParseLevel(level, Console.Error);
 
@@ -114,6 +117,7 @@ public static class LoggerConfigurationFactory
     /// </summary>
     /// <param name="level">Configured level string, possibly null/blank/invalid.</param>
     /// <param name="warningWriter">Writer that receives a single warning line if the value is non-blank but unparseable.</param>
+    /// <returns>The parsed <see cref="LogEventLevel"/>, or <see cref="LogEventLevel.Information"/> when the value is absent or unrecognised.</returns>
     internal static LogEventLevel ParseLevel(string? level, TextWriter warningWriter)
     {
         if (Enum.TryParse<LogEventLevel>(level, ignoreCase: true, out var parsed))