refactor: construct application layers from supplied sources

src/ui.js

@@ -1,2 +1,15 @@
-/** Compatibility entry for the application's UI composition. */
-export { StyleManager } from './ui/composition.js';
+import { StyleManager as ApplicationControls } from './ui/composition.js';
+import { catalogControlServices } from './app/catalog.js';
+import { getStandaloneCatalog } from './standalone/catalog.js';
+/** Compatibility entry for direct standalone control construction. */
+export class StyleManager extends ApplicationControls {
+  constructor(viewer, options = {}) {
+    super(viewer, {
+      ...options,
+      services: {
+        ...catalogControlServices(getStandaloneCatalog()),
+        ...options.services,
+      },
+    });
+  }
+}