Blank out API_USERNAME and API_PASSWORD in .env and .env.staging.
Keys and base URLs are kept; values are supplied locally.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Playwright API test suite for payment/cashier endpoints, with
per-environment config (dev/staging/prod) loaded via dotenv.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>