Add rate limiting for logging

**Description**
Currently auth lacks proper search support.

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

**Priority**: Low/Medium

The title asks for rate limiting for logging, while the body asks for configurable authentication search, so the intended change is unclear. Clarify which behavior is in scope, then identify the relevant authentication or logging entry points and existing tests; done should include agreed defaults, configuration behavior, and coverage for the selected feature.

Written by the indexing model from the issue text.