Function maybe_kick_lead_on_connected 

fn maybe_kick_lead_on_connected(
    workspace: &Arc<Workspace>,
    slot: &SessionSlot,
    domain: &Mutex<DomainSession>,
)

A lead’s first turn after a boot spawn handed it a stored session id to resume: the restart note the spawn stamped on the domain when the boot read the seat as mid-turn. The hook takes the note, so a reconnect repeats nothing, and a parked seat, a first boot or --new never stamped one.