fix for boost>=1.87
commit 1517dcca6cbfe4ac01c5defa4f7d8b1544d47663

Index: lib/network/NetworkDefines.h
--- lib/network/NetworkDefines.h.orig
+++ lib/network/NetworkDefines.h
@@ -15,7 +15,11 @@
 
 VCMI_LIB_NAMESPACE_BEGIN
 
+#if BOOST_VERSION >= 108700
+using NetworkContext = boost::asio::io_context;
+#else
 using NetworkContext = boost::asio::io_service;
+#endif
 using NetworkSocket = boost::asio::ip::tcp::socket;
 using NetworkAcceptor = boost::asio::ip::tcp::acceptor;
 using NetworkBuffer = boost::asio::streambuf;
