refactor: 💡 type-specific account serialization

addons/api/addon/models/fragment-account-attributes.js

@@ -2,8 +2,16 @@ import Fragment from 'ember-data-model-fragments/fragment';
 import { attr } from '@ember-data/model';
 
 export default class FragmentAccountAttributesModel extends Fragment {
+  // =attributes (password)
   @attr('string', {
+    for: 'password',
     description: 'The account login name',
   })
   login_name;
+
+  // =attributes (OIDC)
+  @attr('string', { for: 'oidc' }) subject;
+  @attr('string', { for: 'oidc' }) issuer;
+  @attr('string', { for: 'oidc', readOnly: true }) email;
+  @attr('string', { for: 'oidc', readOnly: true }) full_name;
 }