backend-plugin-api: fix scope

Signed-off-by: Vincenzo Scamporlino <vincenzos@spotify.com>

packages/backend-plugin-api/alpha-api-report.md

@@ -11,14 +11,24 @@ export interface FeatureDiscoveryService {
   }>;
 }
 
-// Warning: (ae-forgotten-export) The symbol "ServiceRef" needs to be exported by the entry point alpha.d.ts
-//
 // @alpha
 export const featureDiscoveryServiceRef: ServiceRef<
   FeatureDiscoveryService,
-  'plugin'
+  'root'
 >;
 
+// @public
+export type ServiceRef<
+  TService,
+  TScope extends 'root' | 'plugin' = 'root' | 'plugin',
+> = {
+  id: string;
+  scope: TScope;
+  T: TService;
+  toString(): string;
+  $$type: '@backstage/ServiceRef';
+};
+
 // Warnings were encountered during analysis:
 //
 // src/alpha.d.ts:5:9 - (ae-forgotten-export) The symbol "BackendFeature" needs to be exported by the entry point alpha.d.ts

packages/backend-plugin-api/src/alpha.ts

@@ -29,4 +29,8 @@ export interface FeatureDiscoveryService {
 export const featureDiscoveryServiceRef =
   createServiceRef<FeatureDiscoveryService>({
     id: 'core.featureDiscovery',
+    scope: 'root',
   });
+
+export type { ServiceRef } from './services';
+export type { BackendFeature };