Add TypeScript types for data

**Feature request**
It would be great to have serialization for config.

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

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

Start by locating the configuration handling and any existing data serialization or TypeScript type definitions; the issue names no files or tests. Confirm how config options are parsed, then define the expected serialized data behavior and verify that enable_serialization defaults to false and enables serialization when set.

Written by the indexing model from the issue text.