Heartbeat Session Stream

A beat, plus what this run knows about the session that nothing else records.

name and references are PROPOSALS, not edits: the service writes each only onto a NULL column (see SessionStreamsService.heartbeat). The runner is the only component present on every execution path — browser, headless invoke, scheduled trigger — so it is the only one that can title and attribute a session that no browser will ever render.

A heartbeat's outcome: the reconciled stream and whether this turn is still current.

replica_id echoes the caller's own id. A runner of the previous release reads it, so it stays for one release.

stream is None when a refused beat names a session that has no row yet: it may not create or stamp one, since that row belongs to the turn's own runner.

is_current_turn (W7.4) is False when this turn_id's alive/running lock was gone or reassigned at the moment of this beat — i.e. a cancel/steer/kill interrupted this turn since the last heartbeat. The runner's watchdog reads this to abort the in-flight run; without it a cancel that raced a heartbeat's nx=True re-acquire would silently re-arm the SAME lock under the SAME turn_id and the interruption would never surface. It is also False when the turn is bound to another runner pod.