fix(options): canonicalize Communication/DataConnection config sections to ScadaBridge:*; drop the duplicate Host bindings that were masking the drift (plan R2-08 T9, arch-review 08r2 NF8)

src/ZB.MOM.WW.ScadaBridge.DataConnectionLayer/ServiceCollectionExtensions.cs

@@ -14,20 +14,26 @@ public static class ServiceCollectionExtensions
     /// <returns>The same <paramref name="services"/> instance for chaining.</returns>
     public static IServiceCollection AddDataConnectionLayer(this IServiceCollection services)
     {
+        // Canonical section is ScadaBridge:DataConnection — the section every real
+        // appsettings actually writes (arch-review 08 round 2 NF8). The Host used to
+        // supply the real values via a duplicate Configure<> binding; that duplicate is
+        // gone, so AddDataConnectionLayer must bind the canonical section itself.
         services.AddOptions<DataConnectionOptions>()
-            .BindConfiguration("DataConnectionLayer")
+            .BindConfiguration("ScadaBridge:DataConnection")
             .ValidateOnStart();
         services.TryAddEnumerable(
             ServiceDescriptor.Singleton<IValidateOptions<DataConnectionOptions>, DataConnectionOptionsValidator>());
 
         // OpcUaGlobalOptions / MxGatewayGlobalOptions carry only string identity/path
         // fields (no numeric or duration knobs), so there is nothing to range-validate
-        // — no dedicated validator is registered for them.
+        // — no dedicated validator is registered for them. Canonical sections are
+        // ScadaBridge:OpcUa / ScadaBridge:MxGateway (NF8): the bare "OpcUa"/"MxGateway"
+        // sections exist in no appsettings, so binding them read nothing.
         services.AddOptions<OpcUaGlobalOptions>()
-            .BindConfiguration("OpcUa");
+            .BindConfiguration("ScadaBridge:OpcUa");
 
         services.AddOptions<MxGatewayGlobalOptions>()
-            .BindConfiguration("MxGateway");
+            .BindConfiguration("ScadaBridge:MxGateway");
 
         // Register the factory for protocol extensibility
         services.AddSingleton<IDataConnectionFactory, DataConnectionFactory>();