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/Security.java
serviceAccountService,
            dlsBitsetCache.get(),
            restrictedIndices,
            new DeprecationRoleDescriptorConsumer(clusterService, threadPool)
        );
        systemIndices.getMainIndexManager().addStateListener(allRolesStore::onSecurityIndexStateChange);
        final ProfileService profileService = new ProfileService(
            settings,
            getClock(),
            client,
            systemIndices.getProfileIndexManager(),
            clusterService,
            realms::getDomainConfig,
            threadPool
        );
        components.add(profileService);
        
        
        
        
        
        InitialNodeSecurityAutoConfiguration.maybeGenerateEnrollmentTokensAndElasticCredentialsOnNodeStartup(
            nativeUsersStore,
            systemIndices.getMainIndexManager(),
            getSslService(),
            client,
            environment,
            (runnable -> nodeStartedListenable.addListener(ActionListener.wrap(runnable))),
            threadPool
        );