utils: replace defer, ContextGuard, DetachableTask with guarden crate (#2163)

easytier/src/connector/udp_hole_punch/common.rs

@@ -6,6 +6,7 @@ use std::{
 
 use crossbeam::atomic::AtomicCell;
 use dashmap::{DashMap, DashSet};
+use guarden::defer;
 use rand::seq::SliceRandom as _;
 use tokio::{net::UdpSocket, sync::Mutex, task::JoinSet};
 use tracing::{Instrument, Level, instrument};
@@ -15,7 +16,6 @@ use crate::{
     common::{
         PeerId, error::Error, global_ctx::ArcGlobalCtx, join_joinset_background, netns::NetNS, upnp,
     },
-    defer,
     peers::peer_manager::PeerManager,
     proto::common::NatType,
     tunnel::{

easytier/src/connector/udp_hole_punch/sym_to_cone.rs

@@ -9,6 +9,7 @@ use std::{
 };
 
 use anyhow::Context;
+use guarden::defer;
 use rand::{Rng, seq::SliceRandom};
 use tokio::{net::UdpSocket, sync::RwLock};
 use tokio_util::task::AbortOnDropHandle;
@@ -22,7 +23,6 @@ use crate::{
         },
         handle_rpc_result,
     },
-    defer,
     peers::peer_manager::PeerManager,
     proto::{
         peer_rpc::{