clippy all codes (#1214)

1. clippy code
2. add fmt and clippy check in ci

easytier/src/peers/route_trait.rs

@@ -1,4 +1,7 @@
-use std::{net::{Ipv4Addr, Ipv6Addr}, sync::Arc};
+use std::{
+    net::{Ipv4Addr, Ipv6Addr},
+    sync::Arc,
+};
 
 use dashmap::DashMap;
 
@@ -10,18 +13,13 @@ use crate::{
     },
 };
 
-#[derive(Clone, Debug)]
+#[derive(Clone, Debug, Default)]
 pub enum NextHopPolicy {
+    #[default]
     LeastHop,
     LeastCost,
 }
 
-impl Default for NextHopPolicy {
-    fn default() -> Self {
-        NextHopPolicy::LeastHop
-    }
-}
-
 pub type ForeignNetworkRouteInfoMap =
     DashMap<ForeignNetworkRouteInfoKey, ForeignNetworkRouteInfoEntry>;