introduce uptime monitor for easytier public nodes (#1250)

easytier/src/peers/route_trait.rs

@@ -9,7 +9,7 @@ use crate::{
     common::{global_ctx::NetworkIdentity, PeerId},
     proto::peer_rpc::{
         ForeignNetworkRouteInfoEntry, ForeignNetworkRouteInfoKey, RouteForeignNetworkInfos,
-        RoutePeerInfo,
+        RouteForeignNetworkSummary, RoutePeerInfo,
     },
 };
 
@@ -102,6 +102,10 @@ pub trait Route {
         Default::default()
     }
 
+    async fn get_foreign_network_summary(&self) -> RouteForeignNetworkSummary {
+        Default::default()
+    }
+
     // my peer id in foreign network is different from the one in local network
     // this function is used to get the peer id in local network
     async fn get_origin_my_peer_id(