feat: add set-application-instance initializer to console

- Create app/instance-initializers/set-application-instance.js
- Sets window.Fleetbase = appInstance.application for global access
- Calls universeService.setApplicationInstance() to cascade to RegistryService
- Ensures all services have access to root application container
- Required for UniverseRegistry singleton to work across engines

console/app/instance-initializers/set-application-instance.js

@@ -0,0 +1,18 @@
+export function initialize(appInstance) {
+    // Set window.Fleetbase to the application for global access
+    // This is used by services and engines to access the root application
+    if (typeof window !== 'undefined') {
+        window.Fleetbase = appInstance.application;
+    }
+
+    // Look up UniverseService and set the application instance
+    // This cascades to RegistryService automatically via universe.setApplicationInstance()
+    const universeService = appInstance.lookup('service:universe');
+    if (universeService) {
+        universeService.setApplicationInstance(appInstance.application);
+    }
+}
+
+export default {
+    initialize
+};