feat(ui): add TableSection abstraction for list views (#16756)

## Summary

Refactors hierarchy tables and group-by tables to use a shared layout
abstraction called `TableSection`. Previously these two table types had
inconsistent padding, headers, and dividers—hierarchy tables used custom
margins while group-by tables had their own styling. Now both share the
same compound component structure with consistent 48px headers, proper
dividers between grouped sections, and unified action slot positioning
for bulk selection and pagination.

The pagination controls in both table types now use `SimplePagination`,
a minimal prev/next component that fits within the table header. This
replaces the larger pagination component that was awkward in grouped
contexts.

Also adds `GroupByControl`, a dropdown for selecting the group-by field
that adapts to the current theme. The theme prop propagates from Popup
through PopupList to RadioGroup items, allowing the control to render
correctly in both light and dark mode contexts.

Minor fixes include preventing scroll jumps when list query params
update and handling undefined fields in WhereBuilder conditions.