face: minor code reorganization and doxygen cleanups

Change-Id: I280bd2f4d282f246ef491e327a5b990ca7600dd3
diff --git a/daemon/face/face.cpp b/daemon/face/face.cpp
index 7b15dc5..3c65a98 100644
--- a/daemon/face/face.cpp
+++ b/daemon/face/face.cpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /*
- * Copyright (c) 2014-2022,  Regents of the University of California,
+ * Copyright (c) 2014-2024,  Regents of the University of California,
  *                           Arizona Board of Regents,
  *                           Colorado State University,
  *                           University Pierre & Marie Curie, Sorbonne University,
@@ -27,6 +27,24 @@
 
 namespace nfd::face {
 
+FaceCounters::FaceCounters(const LinkService::Counters& linkServiceCounters,
+                           const Transport::Counters& transportCounters)
+  : nInInterests(linkServiceCounters.nInInterests)
+  , nOutInterests(linkServiceCounters.nOutInterests)
+  , nInterestsExceededRetx(linkServiceCounters.nInterestsExceededRetx)
+  , nInData(linkServiceCounters.nInData)
+  , nOutData(linkServiceCounters.nOutData)
+  , nInNacks(linkServiceCounters.nInNacks)
+  , nOutNacks(linkServiceCounters.nOutNacks)
+  , nInPackets(transportCounters.nInPackets)
+  , nOutPackets(transportCounters.nOutPackets)
+  , nInBytes(transportCounters.nInBytes)
+  , nOutBytes(transportCounters.nOutBytes)
+  , m_linkServiceCounters(linkServiceCounters)
+  , m_transportCounters(transportCounters)
+{
+}
+
 Face::Face(unique_ptr<LinkService> service, unique_ptr<Transport> transport)
   : afterReceiveInterest(service->afterReceiveInterest)
   , afterReceiveData(service->afterReceiveData)