Optimize store for large datasets

**Description**
Currently data lacks proper backup support.

**Proposed solution**
Add configurable backup with sensible defaults.

**Priority**: Low/Medium

Start by locating the store implementation and its configuration entry points, then inspect how data is currently persisted and how large datasets are handled. Determine the backup settings and sensible defaults from the existing configuration conventions, and add tests showing that configurable backups work as intended.

Written by the indexing model from the issue text.