As we are rolling out the user profile feature, we'd like to expand the [Usage API](https://www.elastic.co/guide/en/elasticsearch/reference/current/usage-api.html) to report usage stats of user profiles such as (1) number of enabled user profiles and (2) number of user profiles that are [activated](https://www.elastic.co/guide/en/elasticsearch/reference/current/security-api-activate-user-profile.html) over the past X days. 

Response of the Usage API already contains a `security` field that groups relevant stats from security related features. We expect the new stats for user profiles should be added under it as well, for example:
```
{
  "security: {
    "user_profile": {
      "activated": 78,
      "recently_activated": 42  <1>
    }
  }
}
```
<1> The use of `recently_` is chosen to avoid the field to be tied to a specific time period so it is easier to evolve the definition in future.

x-pack/plugin/security/src/main/java/org/elasticsearch/xpack/security/profile/ProfileService.java
}
    
    void createNewProfile(Subject subject, String uid, ActionListener<Profile> listener) throws IOException {
        
        
        
        final ProfileDocument profileDocument = ProfileDocument.fromSubjectWithUid(subject, uid);
        final String docId = uidToDocId(profileDocument.uid());
        final BulkRequest bulkRequest = toSingleItemBulkRequest(
            client.prepareIndex(SECURITY_PROFILE_ALIAS)
                .setId(docId)
                .setSource(wrapProfileDocument(profileDocument))
                .setOpType(DocWriteRequest.OpType.CREATE)
                .setRefreshPolicy(RefreshPolicy.WAIT_UNTIL)
                .request()
        );
        profileIndex.prepareIndexIfNeededThenExecute(
            listener::onFailure,
            () -> executeAsyncWithOrigin(
                client,
                getActionOrigin(),
                BulkAction.INSTANCE,
                bulkRequest,
                TransportSingleItemBulkWriteAction.<IndexResponse>wrapBulkResponse(ActionListener.wrap(indexResponse -> {
                    assert docId.equals(indexResponse.getId());
                    final VersionedDocument versionedDocument = new VersionedDocument(
                        profileDocument,
                        indexResponse.getPrimaryTerm(),
                        indexResponse.getSeqNo()
                    );