promote all backend feature exports to main entry point

Signed-off-by: Patrik Oldsberg <poldsberg@gmail.com>

plugins/proxy-backend/report.api.md

@@ -3,6 +3,7 @@
 > Do not edit this file. It is a report generated by [API Extractor](https://api-extractor.com/).
 
 ```ts
+import { BackendFeature } from '@backstage/backend-plugin-api';
 import { DiscoveryService } from '@backstage/backend-plugin-api';
 import express from 'express';
 import { Logger } from 'winston';
@@ -11,6 +12,10 @@ import { RootConfigService } from '@backstage/backend-plugin-api';
 // @public @deprecated
 export function createRouter(options: RouterOptions): Promise<express.Router>;
 
+// @public (undocumented)
+const _feature: BackendFeature;
+export default _feature;
+
 // @public @deprecated (undocumented)
 export interface RouterOptions {
   // (undocumented)
@@ -27,6 +32,7 @@ export interface RouterOptions {
 
 // Warnings were encountered during analysis:
 //
+// src/index.d.ts:8:15 - (ae-undocumented) Missing documentation for "_feature".
 // src/service/router.d.ts:9:1 - (ae-undocumented) Missing documentation for "RouterOptions".
 // src/service/router.d.ts:10:5 - (ae-undocumented) Missing documentation for "logger".
 // src/service/router.d.ts:11:5 - (ae-undocumented) Missing documentation for "config".

plugins/proxy-backend/src/index.ts

@@ -14,6 +14,8 @@
  * limitations under the License.
  */
 
+import { default as feature } from './alpha';
+
 /**
  * A Backstage backend plugin that helps you set up proxy endpoints in the backend
  *
@@ -21,3 +23,7 @@
  */
 
 export * from './service';
+
+/** @public */
+const _feature = feature;
+export default _feature;