Refactor CMakeLists

Closes #2471
Closes #1816

example/echo-op/CMakeLists.txt

@@ -1,5 +1,6 @@
 #
 # Copyright (c) 2016-2017 Vinnie Falco (vinnie dot falco at gmail dot com)
+# Copyright (c) 2024 Mohammad Nejati
 #
 # Distributed under the Boost Software License, Version 1.0. (See accompanying
 # file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
@@ -7,17 +8,11 @@
 # Official repository: https://github.com/boostorg/beast
 #
 
-GroupSources(include/boost/beast beast)
-GroupSources(example/echo-op "/")
-
-add_executable (echo-op
-    ${BOOST_BEAST_FILES}
+add_executable(echo-op
     Jamfile
-    echo_op.cpp
-)
+    echo_op.cpp)
 
-target_link_libraries(echo-op
-    lib-asio
-    lib-beast)
+target_link_libraries(echo-op PRIVATE Boost::beast)
 
-set_property(TARGET echo-op PROPERTY FOLDER "example")
+set_target_properties(echo-op
+    PROPERTIES FOLDER "example-echo-op")