Optimize middleware for large datasets

**Description**
Currently helpers lacks proper encryption support.

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

**Priority**: Low/Medium

No files, tests, or entry points are named, and the title conflicts with the body: clarify whether the work concerns large-dataset middleware optimization or encryption in helpers. Before implementation, define the supported encryption behavior, configuration surface, sensible defaults, and tests that demonstrate the feature is complete.

Written by the indexing model from the issue text.