radicle: add ReviewEdit getter methods — heartwood

Downstream clients require access to the data for a ReviewEdit – for example, the desktop client builds a representation of Actions for TypeScript generation.

To allow these kinds of use cases, methods are added to ReviewEdit to allow access to its underlying data.

         }
     }
     /// Get the summary of the [`ReviewEdit`].
     ///
     /// The summary was optional in the first version, so it may be `None`.
     pub fn summary(&self) -> Option<&String> {
         match self {
             ReviewEdit::V1(ReviewEditV1 { summary, .. }) => summary.as_ref(),
             ReviewEdit::V2(ReviewEditV2 { summary, .. }) => Some(summary),
         }
     }
     /// Get the [`Verdict`] of the [`ReviewEdit`].
     pub fn verdict(&self) -> Option<&Verdict> {
         match self {
             ReviewEdit::V1(ReviewEditV1 { verdict, .. }) => verdict.as_ref(),
             ReviewEdit::V2(ReviewEditV2 { verdict, .. }) => verdict.as_ref(),
         }
     }
     /// Get the list of [`Label`]s of the [`ReviewEdit`].
     pub fn labels(&self) -> &[Label] {
         match self {
             ReviewEdit::V1(ReviewEditV1 { labels, .. }) => labels,
             ReviewEdit::V2(ReviewEditV2 { labels, .. }) => labels,
         }
     }
     /// Get the [`Embed`]s of the [`ReviewEdit`].
     ///
     /// [`Embed`]s were introduced in the second version of edits. For this
     /// reason, an [`Option`] is returned instead of a [`Vec`] – this allows to
     /// avoid an unnecessary clone of the [`Vec`] when it is present.
     pub fn embeds(&self) -> Option<&Vec<Embed<Uri>>> {
         match self {
             ReviewEdit::V1(_) => None,
             ReviewEdit::V2(ReviewEditV2 { embeds, .. }) => Some(embeds),
         }
     }
     /// Apply the action to the given [`Patch`].
     pub fn run(
         self,