add stats metrics (#1207)

support new cli command `easytier-cli stats`

It's useful to find out which components are consuming bandwidth.

easytier/src/proto/rpc_impl/bidirect.rs

@@ -9,7 +9,8 @@ use crate::{
     tunnel::{packet_def::PacketType, ring::create_ring_tunnel_pair, Tunnel},
 };
 
-use super::{client::Client, server::Server};
+use super::{client::Client, server::Server, service_registry::ServiceRegistry};
+use crate::common::stats_manager::StatsManager;
 
 pub struct BidirectRpcManager {
     rpc_client: Client,
@@ -38,6 +39,20 @@ impl BidirectRpcManager {
         }
     }
 
+    pub fn new_with_stats_manager(stats_manager: Arc<StatsManager>) -> Self {
+        Self {
+            rpc_client: Client::new_with_stats_manager(stats_manager.clone()),
+            rpc_server: Server::new_with_registry_and_stats_manager(Arc::new(ServiceRegistry::new()), stats_manager),
+
+            rx_timeout: None,
+            error: Arc::new(Mutex::new(None)),
+            tunnel: Mutex::new(None),
+            running: Arc::new(AtomicBool::new(false)),
+
+            tasks: Mutex::new(None),
+        }
+    }
+
     pub fn set_rx_timeout(mut self, timeout: Option<std::time::Duration>) -> Self {
         self.rx_timeout = timeout;
         self