Add rate limiting for encryption

**Feature request**
It would be great to have export for api.

**Use case**
Many users need this functionality for production deployments.

**Implementation idea**
Add a new config option `enable_export` with default `false`.

First clarify whether the request is rate limiting for encryption or exporting an API, since the title and body describe different work. Then locate the configuration entry point and determine where `enable_export` should be defined with a default of `false`; done should include tests or verification for the intended production behavior.

Written by the indexing model from the issue text.