Rotate a run's stream URL

Gives a run a new stream URL and retires the old one: connections open on the old URL are closed within about 15 seconds and the old URL answers 404 from then on. Use it when the URL may have leaked. Owner only, and only for a run that is running and was started with stream: true (the URL cannot be added to a run later, and a revoked one cannot be brought back). The plan is checked again: a plan that may not broadcast gets 429.

See the "Live execution" guide, "A plain WebSocket stream of a run".