plugins: refactory to use default export for new backend system

Co-authored-by: Fredrik Adelöw <freben@gmail.com>
Co-authored-by: Camila Belo <camilaibs@gmail.com>
Co-authored-by: Johan Haals <johan.haals@gmail.com>
Co-authored-by: Philipp Hugenroth <philipph@spotify.com>
Signed-off-by: Patrik Oldsberg <poldsberg@gmail.com>

plugins/user-settings-backend/api-report.md

@@ -20,7 +20,8 @@ export interface RouterOptions {
 }
 
 // @alpha
-export const userSettingsPlugin: () => BackendFeature;
+const userSettingsPlugin: () => BackendFeature;
+export default userSettingsPlugin;
 
 // (No @packageDocumentation comment for this package)
 ```

plugins/user-settings-backend/src/index.ts

@@ -16,4 +16,4 @@
 
 export * from './service';
 export * from './database';
-export { userSettingsPlugin } from './plugin';
+export { userSettingsPlugin as default } from './plugin';