eBay adapter covers OAuth, inventory API, fulfillment API, taxonomy
service and webhook signature verification. Frappe ERP adapter wraps
the Frappe HTTP client for order/invoice sync.
Includes CustomerResolver, InvoiceMailer, and the EbayWebhookController
for inbound eBay marketplace notifications.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
