OptionalmaxCap the visible rows before the list scrolls.
OptionalonMove the highlight (hover). Optional so the panel works read-only.
Commit a row — the editor splices name( into the formula at the caret.
The highlighted row (keyboard/hover selection). Clamped by the caller.
OptionalselectedSummary for the selected item only, loaded lazily by the editor. Shown as a single dimmed line under the selected row — one at a time (so the panel never bounces) and non-wrapping.
The matching items, already filtered/sorted by the editor.