Figured bass in parentheses

Put the figured bass in rounded parentheses with Scheme function.

\version "2.24.0"

%LSR by Gilles Thibault (id d=902)
startParenthesis = {
  \once \override Parentheses.stencils = #(lambda (grob)
                                            (let ((par-list (parentheses-interface::calc-parenthesis-stencils grob)))
                                              (list (car par-list) point-stencil )))
}

endParenthesis = {
  \once \override Parentheses.stencils = #(lambda (grob)
                                            (let ((par-list (parentheses-interface::calc-parenthesis-stencils grob)))
                                              (list point-stencil (cadr par-list))))
}
%--------

<<
  \time 12/8
  \new Staff { \clef "F" d4 8 4 8 8 8 4 8 }
  \new FiguredBass \figuremode {
    \parenthesize <6>4.
    \override Parentheses.font-size = #2
    \parenthesize  <7 4>4
    \startParenthesis \parenthesize <6 4>8 <5 3> <4 2>
    \endParenthesis \parenthesize <3 1>4.
  }
>>