Open an event stream

Mints a short-lived, account-scoped subscription token for the live event stream. The SDKs call this for you behind new_events_connection(); the CLI uses it for the listen daemon. Re-mint before ttlSeconds elapses to keep the stream open.

Delivery is presence-based, not at-least-once: events that occur while you are disconnected are replayed only if you reconnect within 2 minutes. For guaranteed at-least-once delivery, webhooks and destinations are coming soon.