chore: decrease goroutine used in core tunnel

adapter/inbound/addition.go

@@ -1,6 +1,8 @@
 package inbound
 
 import (
+	"net"
+
 	C "github.com/Dreamacro/clash/constant"
 )
 
@@ -33,3 +35,12 @@ func WithSpecialProxy(specialProxy string) Addition {
 		metadata.SpecialProxy = specialProxy
 	}
 }
+
+func WithSrcAddr(addr net.Addr) Addition {
+	return func(metadata *C.Metadata) {
+		if ip, port, err := parseAddr(addr); err == nil {
+			metadata.SrcIP = ip
+			metadata.SrcPort = port
+		}
+	}
+}