REALITY client: Clearer log when receiving real certificate (#5427)

Co-authored-by: RPRX <[email protected]>

transport/internet/reality/reality.go

@@ -180,11 +180,14 @@ func UClient(c net.Conn, config *Config, ctx context.Context, dest net.Destinati
 		fmt.Printf("REALITY localAddr: %v\tuConn.Verified: %v\n", localAddr, uConn.Verified)
 	}
 	if !uConn.Verified {
+		errors.LogError(ctx, "REALITY: received real certificate (potential MITM or redirection)")
 		go func() {
 			client := &http.Client{
 				Transport: &http2.Transport{
 					DialTLSContext: func(ctx context.Context, network, addr string, cfg *gotls.Config) (net.Conn, error) {
-						fmt.Printf("REALITY localAddr: %v\tDialTLSContext\n", localAddr)
+						if config.Show {
+							fmt.Printf("REALITY localAddr: %v\tDialTLSContext\n", localAddr)
+						}
 						return uConn, nil
 					},
 				},