feat(dcl): MxGateway client seam interfaces + global options

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

@@ -0,0 +1,11 @@
+namespace ZB.MOM.WW.ScadaBridge.DataConnectionLayer;
+
+/// <summary>
+/// Deployment-wide MxGateway defaults, bound from the "MxGateway" section of
+/// appsettings.json. Per-endpoint behavior lives on MxGatewayEndpointConfig.
+/// </summary>
+public class MxGatewayGlobalOptions
+{
+    /// <summary>Prefix used to derive a per-connection client registration name when the connection's ClientName is blank.</summary>
+    public string ClientNamePrefix { get; set; } = "scadabridge";
+}