The group header ("MATCH"/"GROUP") was a dead label while the engine
honored group modes all along — buildGroupClause parenthesizes nested
groups and joins each by its own mode, and validation accepted
all/any from day one. The only thing missing was the UI: + Group
birthed ALL groups and no control anywhere could flip one, so the
user's target structures (GROUP(GROUP(... or ...) ...) — 3-level
mixed-mode nesting) were constructible only through the invisible
row-level chips, and standalone ANY-groups not at all (2026-11-01
user report: "MATCH cannot be clicked").
- The header is now the control: MATCH ALL ⇄ MATCH ANY (root — a
synthetic header row, since the root was never projected and its
mode was invisible too), GROUP ALL ⇄ GROUP ANY (nested). ANY is
accented; aria-pressed carries the state. Labels are path-based
(root reads Match, explicit groups read Group) instead of
depth-based, which previously mislabeled top-level groups.
- The row-level chips are untouched — they mix AND/OR inside a group
(A AND (B OR C)), which a global mode toggle cannot express; the
header is the discoverable entry point, the chips the refinement.
- Dropdown audit (the "would it bug out" check): suggestTree is
mode-generic — root-ANY drops group siblings, sibling ANY-groups
survive into the constraint with their mode intact, empty groups
never emit (no 400s) — now pinned. Deep-nesting Go pin: a 3-level
mixed-mode tree evaluated through composed search + the suggestion
endpoint (200, never the empty-group 400). 192 web tests green.