feat: Serve never returns

This is a breaking change as the return type of cluster.nodes has
changed, resulting in old templates potentially no longer working.

src/main.rs

@@ -46,7 +46,7 @@ async fn generate(opts: &GlobalOpts) -> Result<(), Error> {
 
         let content = template
             .render(context! {
-                clusters,
+                clusters => clusters.values().collect::<Vec<_>>(),
                 root => opts.repo
             })
             .unwrap();