message: Add a doc-comment to `dummy_lookup_value`
diff: @@ -236,6 +236,10 @@ pub struct LookupConfiguration<F: FftField> {
  pub max_joint_size: u32,
  #[serde_as(as = "Vec<o1_utils::serialization::SerdeAs>")]
  + /// A placeholder value that is known to appear in the lookup table.
  + /// This is used to pad the lookups to `max_lookups_per_row` when fewer lookups are used in a
  + /// particular row, so that we can treat each row uniformly as having the same number of
  + /// lookups.
  pub dummy_lookup_value: Vec<F>,
  }
  