Handle edge cases in encryption

**Feature request**
It would be great to have import for data.

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

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

No file, test, data format, or import entry point is named. Start by locating configuration handling and the existing encryption or data-loading paths, then determine the supported import behavior; done should include a disabled-by-default enable_import option and a defined, tested import flow.

Written by the indexing model from the issue text.