Repeating a phrasing slur in the secondo

Question

Recently I've written some choral parts and stumbled into the following issue. A phrasing slur starts in the repeat and should be repeated in volta 2, the secondo (see example). How do I add the slur there? Something comparable to the behaviour of a \repeatTie.

I checked the documentation regarding ties, but I found nothing similar there.

What is the recommended way to add such a repeated slur?
Some custom \laissezVibrer perhaps?

\version "2.24.0"
\score {
  \relative c'' {
    c4 c c c |
    \repeat volta 2 {
      d4 \( d d d |
      \alternative {
        \volta 1 {
          c2 c2 \)
        }
        \volta 2 {
          c2 c2 % Slur added here like c2 c2 \) 
        }
      }
    }
    d4 d d d
  }
}

Preview:

EDIT:

Workaround 1:

Following these MuseScore ideas, a hidden note with a slur seems to be a valid approach. Plus the hidden note can be used for quick adjustments of the slur's height.

\hideNotes
e16 \(
\unHideNotes
c2 c2 \)

Output:

Workaround 2:

Comparable to the answer below, I use a phrasing slur with a custom \shape and a spacer. Needs some tweaking to get the curve right. But seems to be a flexible way to solve it.

\shape #'((-2.5 . 1.5) (-2.5 . 1) (0 . 1.0) (0 . 0)) PhrasingSlur   
s4 \(
c2 c2\) 

Answer 1

Workaround 2 is almost right, but the crotchet spacer s4 (or a hidden note) will throw out the timing (as can been seen in the following measure).

Instead, start the phrasing slur in the second volta on an empty chord <>:

\volta 2 {
    \shape #'((-2 . 1.4)(-2 . 0.6)(0 . 0)(0 . 0)) PhrasingSlur
    <>\( c2 c2\) |
}