Messaging: Add message replies.

Servers: Add VoiceChannel.

src/routes/channels/message_edit.rs

@@ -19,6 +19,8 @@ pub async fn req(user: User, target: Ref, msg: Ref, edit: Json<Data>) -> Result<
         .map_err(|error| Error::FailedValidation { error })?;
 
     let channel = target.fetch_channel().await?;
+    channel.has_messaging()?;
+
     let perm = permissions::PermissionCalculator::new(&user)
         .with_channel(&channel)
         .for_channel()