refactor(proxy): migrate to zerolog structured logging

internal/proxy/transport.go

@@ -1,12 +1,12 @@
 package proxy
 
 import (
-	"log"
 	"net"
 	"net/http"
 	"sync"
 
 	tls "github.com/refraction-networking/utls"
+	"github.com/rs/zerolog/log"
 	"golang.org/x/net/http2"
 )
 
@@ -90,7 +90,7 @@ func (t *utlsRoundTripper) RoundTrip(req *http.Request) (*http.Response, error)
 		port = "443"
 	}
 	addr := net.JoinHostPort(hostname, port)
-	log.Printf("utls: RoundTrip to %s (Chrome TLS fingerprint, HTTP/2)", addr)
+	log.Debug().Str("addr", addr).Msg("uTLS round trip")
 
 	h2Conn, err := t.getOrCreateConnection(hostname, addr)
 	if err != nil {