fix: export BackendFeature from alpha entrypoint and regenerate API report

Re-export catalogModuleMicrosoftGraphIncrementalEntityProvider as @alpha
default from src/alpha.ts, matching the pattern of catalog-backend-module-msgraph.
Add default export alias in module/index.ts and regenerate report-alpha.api.md.

Signed-off-by: pillaris <pillaris@adobe.com>
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

plugins/catalog-backend-module-msgraph-incremental/report-alpha.api.md

@@ -3,5 +3,11 @@
 > 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';
+
+// @alpha (undocumented)
+const _feature: BackendFeature;
+export default _feature;
+
 // (No @packageDocumentation comment for this package)
 ```

plugins/catalog-backend-module-msgraph-incremental/src/alpha.ts

@@ -14,4 +14,8 @@
  * limitations under the License.
  */
 
-export {};
+import { default as feature } from './module';
+
+/** @alpha */
+const _feature = feature;
+export default _feature;

plugins/catalog-backend-module-msgraph-incremental/src/module/index.ts

@@ -15,6 +15,7 @@
  */
 
 export {
+  catalogModuleMicrosoftGraphIncrementalEntityProvider as default,
   catalogModuleMicrosoftGraphIncrementalEntityProvider,
   microsoftGraphIncrementalEntityProviderTransformExtensionPoint,
   type MicrosoftGraphIncrementalEntityProviderTransformsExtensionPoint,