SAN FRANCISCO—Self-driving tech startup Nuro said on Wednesday it was rolling out California’s first commercial autonomous delivery service in partnership with 7-Eleven, a convenience store operator. Nuro and rivals such as Waymo are launching or planning to launch autonomous delivery services with regulatory approval in the United States, though the services are limited or not in the form of driverless vehicles. The service will start with Toyota Priuses converted into autonomous vehicles and include a safety driver to monitor the technology, Nuro said. “The Priuses are the first step in Nuro’s multi-phase approach to introducing commercial autonomous delivery to select service areas,” Nuro said in a statement, adding that the company and 7-Eleven will make the joint decision to introduce Nuro’s R2 driverless vehicles “as soon as possible.” The service will be available to customers in Mountain View where Nuro is headquartered. It is already delivering Domino’s Pizza products in …