Who's here, what they're doing

Every tab on a decision sends a heartbeat every 5 seconds. The presence snapshot is the last 15 seconds of heartbeats, grouped by member — multi-tab same-user collapses to one row. Live members appear in their stable hue.

Disagreement is visible, not destructive

When two members score the same matrix cell to different values, both stay visible — neither overwrites the other. A warning dot surfaces the conflict and a popover offers three resolution paths (Discuss · Use average · Add comment).

Co-edit row states

When another member starts editing an objective, your view shows that row in a lock state — advisory, last-write-wins; a real CRDT lands in a later wave. New rows that just landed get a one-shot pulse.