Selection Summary

The component is self-contained: one file, no dependencies, the palette in --vibeui-datagrid-016-*. A client component: useState holds the list of ticked ids and the chosen fold function. The total lives in the tfoot and changes its label together with the function — "Total" above an average would be a lie. A row checkbox carries its own aria-label with the name of the campaign, and the totals heading is declared aria-live, so a change of selection is heard. A selected row is marked both by a fill and by a stripe on the left through an inset box-shadow. On an empty selection the numeric cells hold a dash rather than a zero: a zero reads as a computed result. The theme comes from the surrounding color-scheme through light-dark(): by default the grid lays no panel under itself, it sits directly on the page background and darkens along with it. The aggregate prop sets the starting fold and keeps acting after mounting: the reader's choice is stored alongside the prop rather than instead of it.