Function describe_system_job_address_at 

pub fn describe_system_job_address_at<'s>(
    source: &'s str,
    offset: usize,
    others: impl IntoIterator<Item = &'s str>,
) -> Option<String>

#2136 (ADR 0156): hover for the schedule / message address name in a system-tier case (sweeper.schedule(…), deliveries.message(m)), which runs the handler through the participant Worker’s own scheduled / queue entry point rather than in process. None anywhere else, including the same address at unit or integration, and a .schedule / .message whose receiver is not a cron / queue service of the suite’s target (a record field named message, say). The target’s declaration is looked up in source and others (the project’s other files).