- Security: Move API keys to environment variables in config.py
- Portability: Use cross-platform path resolution for DB_FILE
- Add config.example.py template for developers
- Fix Windows path in ExchangeInterface.get_public_exchanges()
- Add cached_last_candle attribute to Candles class
- Add pytest configuration (pytest.ini, conftest.py)
- Fix test imports for DataCache_v3
- Include identity compatibility layer (user_name/user_id resolution)
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>