move hierarchy to fiori

bookshop/srv/admin-service.cds

@@ -1,12 +1,5 @@
 using { sap.capire.bookshop as my } from '../db/schema';
-using { my.common.Hierarchy as Hierarchy } from './hierarchy';
-
-extend my.Genres with Hierarchy;
-
 service AdminService @(requires:'admin', path:'/admin') {
   entity Books          as projection on my.Books;
   entity Authors        as projection on my.Authors;
-  @readonly
-  @cds.search: {name}
-  entity GenreHierarchy as projection on my.Genres
 }