- Add "Danger Zone" section to ShopSettings with deactivate/close actions
- CloseShopConfirmDialog: type shop name to confirm (GitHub-style)
- BFF: proxy endpoints POST /shops/{id}/deactivate and /close
- MerchantApiService: DeactivateShopAsync(), CloseShopAsync()
- CTO report documenting the gap and implementation
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>