Asymmetric slurs

Slurs can be made asymmetric to match an asymmetric pattern of notes better.

\version "2.24"

slurNotes = { d,8( a' d f a f' d, a) }

\relative c' {
  \stemDown
  \slurUp
  \slurNotes
  \once \override Slur.eccentricity = #3.0
  \slurNotes
}