added changelog

Author: sergioteula

CHANGELOG.md

@@ -0,0 +1,36 @@
+# Changelog
+
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
+and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
+
+## [5.1.0] - 2026-01-11
+
+### Added
+
+- Integration tests with real Amazon API calls
+- Type hints throughout the codebase using `Literal` types for country codes
+- `.env.template` file for easier development setup
+- Code style guide for AI assistants (`.agent/rules/code-style-guide.md`)
+- Pre-commit hooks with Ruff integration
+
+### Changed
+
+- **BREAKING**: Minimum Python version raised from 3.7 to 3.9
+- Migrated from `setup.py` to `pyproject.toml` for project configuration
+- Replaced multiple linters (Flake8, isort, Black, Pylint) with Ruff
+- Replaced Docker-based development environment with `uv` package manager
+- Consolidated coverage, mypy, and pytest configuration into `pyproject.toml`
+- Renamed test files to use `_test.py` suffix instead of `test_` prefix
+- Updated GitHub Actions workflows to use `uv` instead of Docker
+- Improved docstrings across the codebase
+
+### Removed
+
+- `setup.py` - replaced by `pyproject.toml`
+- `.coveragerc` - configuration moved to `pyproject.toml`
+- `.flake8` - replaced by Ruff configuration in `pyproject.toml`
+- Docker development environment (`docker/`, `docker-compose.yml`)
+- Legacy shell scripts (`scripts/` directory)
+- Custom git hooks (`.githooks/`) - replaced by pre-commit