The view-draft layer stores `{op: 'and', children: []}` as an explicit
"override baseline with no predicates" marker. That payload was leaking
into /bases/rows requests once local filter/sort drafts were enabled —
harmless server-side (buildWhere maps an empty group to TRUE) but it
destabilised the React Query key and cluttered request payloads. Normalise
empty groups to undefined at the hook level.
Philipinho