pub(crate) fn publish_background_task_updated(broker: &Broker, block_id: &str)Expand description
Notify subscribers that block_id’s db_background_tasks state changed
(observed, pid recorded, or completed), so the frontend can re-query
COMMAND_LIST_BACKGROUND_TASKS instead of polling. Live-only (persist: 0) — a late subscriber gets the current state via the mount-time list
query, not event replay. Deliberately carries no task data itself (just an
invalidation signal): the list query is the single source of truth for the
actual rows. See
docs/specs/SPEC_BACKGROUND_TASK_DASHBOARD_INTELLIGENCE_2026_08_20.md §3.2.