server: poll for new messages and update clients via WS

shared/src/lib.rs

@@ -13,7 +13,7 @@ pub struct SearchResult {
     pub total: usize,
 }
 
-#[derive(Serialize, Deserialize, Debug)]
+#[derive(Serialize, Deserialize, Debug, strum_macros::Display)]
 pub enum WebsocketMessage {
     RefreshMessages,
 }