message: Populate some more spans in quote
diff: @@ -1000,12 +1000,12 @@ impl<'in_arena, 'out_arena, 'env> QuoteContext<'in_arena, 'out_arena, 'env> {
  match value.as_ref() {
  Value::Stuck(span, head, spine) => {
  let head_expr = match head {
  - Head::Prim(prim) => Term::Prim(Span::Empty, *prim),
  + Head::Prim(prim) => Term::Prim(*span, *prim),
  Head::RigidVar(var) => {
  // FIXME: Unwrap
  - Term::RigidVar(Span::Empty, self.rigid_exprs.global_to_local(*var).unwrap())
  + Term::RigidVar(*span, self.rigid_exprs.global_to_local(*var).unwrap())
  }
  - Head::FlexibleVar(var) => Term::FlexibleVar(Span::Empty, *var),
  + Head::FlexibleVar(var) => Term::FlexibleVar(*span, *var),
  };
  spine.iter().fold(head_expr, |head_expr, elim| match elim {
  