Enhance internal payment handling and e2e testing setup

docker-compose.e2e.yaml

@@ -324,6 +324,8 @@ services:
       CYPRESS_BASE_URL: http://localhost:${E2E_BACKOFFICE_PORT:-5383}
       CYPRESS_API_URL: http://localhost:${E2E_API_PORT:-3101}
       CYPRESS_PORTAL_URL: http://localhost:${E2E_PORTAL_PORT:-5373}
+      # Must match freight-api-e2e's SERVICE_AUTH_TOKEN above.
+      CYPRESS_SERVICE_AUTH_TOKEN: e2e-service-token
     volumes:
       - .:/repo