Move logger traits out of detail namespace into logger_traits.hpp

Summary:
related to T15252, #24
- move logger traits out of detail namespace into logger_traits.hpp to allow writers of their own loggers to verify that their implementation satisfies the LoggerType requirements
- move impl/codecs/traits to detail/traits, traits functions are now in detail namespace
- logger outputs the contents of props in debug mode

Reviewers: ivica

Reviewed By: ivica

Subscribers: iljazovic, miljen

Differential Revision: https://repo.mireo.local/D32524

test/integration/client_functions.cpp

@@ -23,6 +23,7 @@
 
 #include <async_mqtt5/mqtt_client.hpp>
 #include <async_mqtt5/types.hpp>
+#include <async_mqtt5/detail/traits.hpp>
 
 #include "test_common/message_exchange.hpp"
 #include "test_common/packet_util.hpp"
@@ -406,7 +407,7 @@ BOOST_FIXTURE_TEST_CASE(connack_properties, shared_connack_prop_test_data) {
 			connack_props cprops_ = c.connack_properties();
 			cprops_.visit([&](const auto& p, const auto& val) -> bool {
 				BOOST_TEST_REQUIRE(p);
-				if constexpr (is_vector<decltype(val)>)
+				if constexpr (detail::is_vector<decltype(val)>)
 					BOOST_TEST(val == cprops[p]);
 				else {
 					BOOST_TEST_REQUIRE(val.has_value());
@@ -429,7 +430,7 @@ BOOST_FIXTURE_TEST_CASE(connack_property, shared_connack_prop_test_data) {
 		std::move(broker_side),
 		[&](client_type& c) {
 			cprops.visit([&](const auto& p, const auto& val) -> bool{
-				if constexpr (is_vector<decltype(val)>)
+				if constexpr (detail::is_vector<decltype(val)>)
 					BOOST_TEST(val == c.connack_property(p));
 				else {
 					BOOST_TEST_REQUIRE(val.has_value());