message: add IdError docs
diff: @@ -177,11 +177,19 @@ pub struct Id<'id> {
  id: &'id str,
  }
  +/// Spotify id or URI parsing error
  +///
  +/// See also [`Id`](crate::model::Id) for details.
  #[derive(Debug, PartialEq, Eq, Clone, Copy, Display, Error)]
  pub enum IdError {
  + /// Spotify URI prefix is not `spotify:` or `spotify/`
  InvalidPrefix,
  + /// Spotify URI can't be split into type and id parts (e.g. it has invalid separator)
  InvalidFormat,
  + /// Spotify URI has invalid type name, or id has invalid type in a given context
  + /// (e.g. a method expects a track id, but artist id is provided)
  InvalidType,
  + /// Spotify id is invalid (empty or contains non-alphanumeric characters)
  InvalidId,
  }
  