feat: Add GatewayModule for enhanced module configuration

knockoutwhistweb/app/modules/GatewayModule.scala

@@ -0,0 +1,9 @@
+package modules
+
+import com.google.inject.AbstractModule
+
+class GatewayModule extends AbstractModule {
+  override def configure(): Unit = {
+    bind(classOf[GatewayModule]).asEagerSingleton()
+  }
+}