feat: Implement get app auth API endpoint

packages/backend/src/controllers/api/v1/apps/get-auth.js

@@ -0,0 +1,8 @@
+import App from '../../../../models/app.js';
+import { renderObject } from '../../../../helpers/renderer.js';
+
+export default async (request, response) => {
+  const auth = await App.findAuthByKey(request.params.appKey);
+
+  renderObject(response, auth, { serializer: 'Auth' });
+};