RunsStreamFrame

Field	Type	Description
`eventId`	`Float`	Durable reconnect cursor; null for transient frames.
`eventType`	`String!`	Stored event type used for the SSE event name.
`payload`	`JSON!`
`isError`	`Boolean!`	Error classification from the stored row.
`createdAt`	`String`	Stored timestamp; null when the frame has no stored timestamp.