OptionalinsightReceives the typed draft (display units) to parse + persist.
OptionaloptionalThe field's value may be removed: the × key on an untouched field enters
an explicit cleared state, and confirming commits an empty draft (the
call site's onCommit("") deletes the value). Off by default — for
required fields an empty draft always means "keep".
The field's current display value, used as the initial draft.
Optional insight rendered above the keys, recomputed from the live draft (so e.g. the load → velocity-profile marker tracks typing).
setDraftlets an interactive insight (e.g. a draggable VP marker) write the draft back, exactly as a keypress would.