- Add Waffo payment SDK integration (waffo-go v1.3.1) - Backend: webhook handler, pay endpoint, order lock race-condition fix - Settings: full Waffo config (API keys, sandbox/prod, currency, pay methods) - Frontend: Waffo payment buttons in topup page, admin settings panel - i18n: Waffo-related translations for en/fr/ja/ru/vi/zh-TW Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
