[OFFAPPS-332] Support running the app under ZAT

:koala: :no_entry_sign: 

Support running the app under ZAT.

Blocked by an implementation of `isZatEnabled()` in the framework instead.

/cc @zendesk/quokka

### References
 - Jira link: https://zendesk.atlassian.net/browse/OFFAPPS-332

### Risks
 - None