fix: ( telebirr ) read transId from webhook for provider_txn_id

packages/payment-providers/src/webhooks/telebirr-webhook.types.ts

@@ -2,6 +2,9 @@ export interface TelebirrWebhookPayload {
   merch_order_id: string;
   payment_order_id: string;
   trade_status: string;
+  /** Telebirr's webhook (notify) sends the transaction id as camelCase `transId`;
+   *  the queryOrder/status-query biz_content uses snake_case `trans_id`. Support both. */
+  transId?: string;
   trans_id?: string;
   total_amount?: string;
   trans_currency?: string;