Add rate limiting for encryption

**Description**
Currently store lacks proper monitoring support.

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

**Priority**: Low/Medium

The issue body conflicts with its title: it asks for rate limiting for encryption but describes configurable monitoring with sensible defaults. No files, entry points, or tests are named, so first reconcile the intended scope and inspect the repository structure. Done should include the agreed behavior, configurable defaults, and verification for the resulting monitoring or rate-limiting support.

Written by the indexing model from the issue text.