[Feature] don't track outbound type dns

[nunu6689]

Verification Steps

• [X] I have read the documentation and confirmed that this feature is not implemented
• [X] I have searched for the feature request I want to propose in the Issue Tracker and did not find it
• [X] I am a non-Chinese user.

Description

When using tproxy with outbound type DNS please don't put it in the connections list. It flooded the connections list and stay there for a while. XD dashboard was lagging a lot, only yacd can handle it. Thanks.

proxies:
  - name: 'dns-hijack'
    type: dns

rules:
  - DST-PORT,53,dns-hijack

diff --git a/tunnel/tunnel.go b/tunnel/tunnel.go
index b1b4add5ee..be2c70e8de 100644
--- a/tunnel/tunnel.go
+++ b/tunnel/tunnel.go
@@ -409,8 +409,10 @@ func handleUDPConn(packet C.PacketAdapter) {
 			}
 			logMetadata(metadata, rule, rawPc)
 
-			pc := statistic.NewUDPTracker(rawPc, statistic.DefaultManager, metadata, rule, 0, 0, true)
-
+			pc := rawPc
+			if proxy.Type() != C.Dns {
+				pc = statistic.NewUDPTracker(rawPc, statistic.DefaultManager, metadata, rule, 0, 0, true)
+			}
 			if rawPc.Chains().Last() == "REJECT-DROP" {
 				_ = pc.Close()
 				return nil, nil, errors.New("rejected drop packet")
@@ -547,7 +549,9 @@ func handleTCPConn(connCtx C.ConnContext) {
 	}
 	logMetadata(metadata, rule, remoteConn)
 
-	remoteConn = statistic.NewTCPTracker(remoteConn, statistic.DefaultManager, metadata, rule, 0, int64(peekLen), true)
+	if proxy.Type() != C.Dns {
+		remoteConn = statistic.NewTCPTracker(remoteConn, statistic.DefaultManager, metadata, rule, 0, int64(peekLen), true)
+	}
 	defer func(remoteConn C.Conn) {
 		_ = remoteConn.Close()
 	}(remoteConn)