Add changelog for v0.4.2

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: vdavez

CHANGELOG.md

@@ -7,6 +7,11 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+## [0.4.2] - 2026-03-04
+
+### Added
+- Protests endpoints: `list_protests`, `get_protest` with shaping and filter params (`source_system`, `outcome`, `case_type`, `agency`, `case_number`, `solicitation_number`, `protester`, `filed_date_after`, `filed_date_before`, `decision_date_after`, `decision_date_before`, `search`).
+
 ## [0.4.1] - 2026-03-03
 
 ### Added