Fix building with Boost 1.87 - 1.90.

- Boost 1.87 removed asio::io_service, use io_context and asio::post().
- Boost 1.87 dropped resolver results -> endpoint conversion in
  async_connect, use the range overload.
- Boost 1.88 made Boost.Process v2 the default, keep using the v1 API.
- Boost 1.89 no longer ships a Boost::system component (header-only since
  1.69).

Rebased for 3.0 from the ::gentoo boost-1.87/1.88/1.89 patches.

diff --git a/cmake/modules/Boost.cmake b/cmake/modules/Boost.cmake
index c8f1c39..34a639d 100644
--- a/cmake/modules/Boost.cmake
+++ b/cmake/modules/Boost.cmake
@@ -13,7 +13,7 @@ endif()
 # boost::process was introduced first in version 1.64.0,
 # boost::beast::detail::base64 was introduced first in version 1.66.0
 set(MINIMUM_BOOST_VERSION "1.86.0")
-set(_boost_components "system;filesystem;thread;locale;regex;chrono;atomic;date_time;iostreams;nowide")
+set(_boost_components "filesystem;thread;locale;regex;chrono;atomic;date_time;iostreams;nowide")
 if(EMSCRIPTEN)
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} --use-port=sdl2 --use-port=zlib -fwasm-exceptions")
     #find_package(Boost ${MINIMUM_BOOST_VERSION} REQUIRED )
diff --git a/src/libslic3r/src/libslic3r/GCode/PostProcessor.cpp b/src/libslic3r/src/libslic3r/GCode/PostProcessor.cpp
index 7c07bd4..17b63ed 100644
--- a/src/libslic3r/src/libslic3r/GCode/PostProcessor.cpp
+++ b/src/libslic3r/src/libslic3r/GCode/PostProcessor.cpp
@@ -159,7 +159,14 @@ static int run_script(const std::string &script, const std::string &gcode, std::
 
 #include <cstdlib>   // getenv()
 #include <sstream>
+#if BOOST_VERSION >= 108800 // v2 is now default
+#define BOOST_PROCESS_VERSION 1
+#include <boost/process/v1/child.hpp>
+#include <boost/process/v1/io.hpp>
+#include <boost/process/v1/pipe.hpp>
+#else
 #include <boost/process.hpp>
+#endif
 
 namespace process = boost::process;
 
diff --git a/src/slic3r-shared/include/Slic3r/Biz/Network/Bonjour.hpp b/src/slic3r-shared/include/Slic3r/Biz/Network/Bonjour.hpp
index bea6f69..4f06e98 100644
--- a/src/slic3r-shared/include/Slic3r/Biz/Network/Bonjour.hpp
+++ b/src/slic3r-shared/include/Slic3r/Biz/Network/Bonjour.hpp
@@ -165,11 +165,11 @@ public:
 	UdpSocket(Bonjour::ReplyFn replyfn
 		, const boost::asio::ip::address& multicast_address
 		, const boost::asio::ip::address& interface_address
-		, std::shared_ptr< boost::asio::io_service > io_service);
+		, std::shared_ptr< boost::asio::io_context > io_service);
 
 	UdpSocket(Bonjour::ReplyFn replyfn
 		, const boost::asio::ip::address& multicast_address
-		, std::shared_ptr< boost::asio::io_service > io_service);
+		, std::shared_ptr< boost::asio::io_context > io_service);
 
 	void send();
 	void async_receive();
@@ -182,7 +182,7 @@ protected:
 	boost::asio::ip::address					    multicast_address;
 	boost::asio::ip::udp::socket					socket;
 	boost::asio::ip::udp::endpoint					mcast_endpoint;
-	std::shared_ptr< boost::asio::io_service >	io_service;
+	std::shared_ptr< boost::asio::io_context >	io_service;
 	std::vector<BonjourRequest>						requests;
 };
 
@@ -196,7 +196,7 @@ public:
 		, Bonjour::ReplyFn replyfn
 		, const boost::asio::ip::address& multicast_address
 		, const boost::asio::ip::address& interface_address
-		, std::shared_ptr< boost::asio::io_service > io_service)
+		, std::shared_ptr< boost::asio::io_context > io_service)
 		: UdpSocket(replyfn, multicast_address, interface_address, io_service)
 		, txt_keys(txt_keys)
 		, service(service)
@@ -213,7 +213,7 @@ public:
 		, std::string protocol
 		, Bonjour::ReplyFn replyfn
 		, const boost::asio::ip::address& multicast_address
-		, std::shared_ptr< boost::asio::io_service > io_service)
+		, std::shared_ptr< boost::asio::io_context > io_service)
 		: UdpSocket(replyfn, multicast_address, io_service)
 		, txt_keys(txt_keys)
 		, service(service)
@@ -251,7 +251,7 @@ public:
 		, Bonjour::ReplyFn replyfn
 		, const boost::asio::ip::address& multicast_address
 		, const boost::asio::ip::address& interface_address
-		, std::shared_ptr< boost::asio::io_service > io_service)
+		, std::shared_ptr< boost::asio::io_context > io_service)
 		: UdpSocket(replyfn, multicast_address, interface_address, io_service)
 		, hostname(hostname)
 
@@ -263,7 +263,7 @@ public:
 	ResolveSocket(const std::string& hostname
 		, Bonjour::ReplyFn replyfn
 		, const boost::asio::ip::address& multicast_address
-		, std::shared_ptr< boost::asio::io_service > io_service)
+		, std::shared_ptr< boost::asio::io_context > io_service)
 		: UdpSocket(replyfn, multicast_address, io_service)
 		, hostname(hostname)
 
diff --git a/src/slic3r-shared/src/Slic3r/Biz/Network/Bonjour.cpp b/src/slic3r-shared/src/Slic3r/Biz/Network/Bonjour.cpp
index de408b6..96ca986 100644
--- a/src/slic3r-shared/src/Slic3r/Biz/Network/Bonjour.cpp
+++ b/src/slic3r-shared/src/Slic3r/Biz/Network/Bonjour.cpp
@@ -7,6 +7,8 @@
 #include <string>
 #include <map>
 #include <thread>
+#include <boost/asio/deadline_timer.hpp>
+#include <boost/asio/post.hpp>
 #include <boost/endian/conversion.hpp>
 #include <boost/date_time/posix_time/posix_time_duration.hpp>
 #include <boost/format.hpp>
@@ -620,7 +622,7 @@ UdpSession::UdpSession(Bonjour::ReplyFn rfn) : replyfn(rfn)
 	buffer.resize(DnsMessage::MAX_SIZE);
 }
 
-UdpSocket::UdpSocket( Bonjour::ReplyFn replyfn, const asio::ip::address& multicast_address, const asio::ip::address& interface_address, std::shared_ptr< boost::asio::io_service > io_service)
+UdpSocket::UdpSocket( Bonjour::ReplyFn replyfn, const asio::ip::address& multicast_address, const asio::ip::address& interface_address, std::shared_ptr< boost::asio::io_context > io_service)
 	: replyfn(replyfn)
 	, multicast_address(multicast_address)
 	, socket(*io_service)
@@ -654,7 +656,7 @@ UdpSocket::UdpSocket( Bonjour::ReplyFn replyfn, const asio::ip::address& multica
 }
 
 
-UdpSocket::UdpSocket( Bonjour::ReplyFn replyfn, const asio::ip::address& multicast_address, std::shared_ptr< boost::asio::io_service > io_service)
+UdpSocket::UdpSocket( Bonjour::ReplyFn replyfn, const asio::ip::address& multicast_address, std::shared_ptr< boost::asio::io_context > io_service)
 	: replyfn(replyfn)
 	, multicast_address(multicast_address)
 	, socket(*io_service)
@@ -710,7 +712,7 @@ void UdpSocket::receive_handler(SharedSession session, const boost::system::erro
 	// let io_service to handle the datagram on session
 	// from boost documentation io_service::post:
 	// The io_service guarantees that the handler will only be called in a thread in which the run(), run_one(), poll() or poll_one() member functions is currently being invoked.
-	io_service->post(boost::bind(&UdpSession::handle_receive, session, error, bytes));
+	boost::asio::post(*io_service, boost::bind(&UdpSession::handle_receive, session, error, bytes));
 	// immediately accept new datagrams
 	async_receive();
 }
@@ -867,7 +869,7 @@ void Bonjour::priv::lookup_perform()
 {
 	service_dn = (boost::format("_%1%._%2%.local") % service % protocol).str();
 
-	std::shared_ptr< boost::asio::io_service > io_service(new boost::asio::io_service);
+	std::shared_ptr< boost::asio::io_context > io_service(new boost::asio::io_context);
 
 	std::vector<LookupSocket*> sockets;
 
@@ -962,7 +964,7 @@ void Bonjour::priv::resolve_perform()
 			rpls.push_back(reply);
 	};
 
-	std::shared_ptr< boost::asio::io_service > io_service(new boost::asio::io_service);
+	std::shared_ptr< boost::asio::io_context > io_service(new boost::asio::io_context);
 	std::vector<ResolveSocket*> sockets;
 
 	// resolve interfaces - from PR#6646
diff --git a/src/slic3r-shared/src/Slic3r/Biz/Network/TCPConsole.cpp b/src/slic3r-shared/src/Slic3r/Biz/Network/TCPConsole.cpp
index daa06bf..b4dc38b 100644
--- a/src/slic3r-shared/src/Slic3r/Biz/Network/TCPConsole.cpp
+++ b/src/slic3r-shared/src/Slic3r/Biz/Network/TCPConsole.cpp
@@ -1,6 +1,7 @@
 #include "Slic3r/Biz/Network/TCPConsole.hpp"
 
 #include <boost/asio/buffer.hpp>
+#include <boost/asio/connect.hpp>
 #include <boost/asio/io_context.hpp>
 #include <boost/asio/ip/tcp.hpp>
 #include <boost/asio/read_until.hpp>
@@ -134,7 +135,7 @@ bool TCPConsole::run_queue()
 
         auto endpoints = m_resolver.resolve(m_host_name, m_port_name);
 
-        m_socket.async_connect(endpoints->endpoint(),
+        boost::asio::async_connect(m_socket, endpoints,
             boost::bind(&TCPConsole::handle_connect, this, boost::placeholders::_1)
         );
 
diff --git a/src/slic3r-shared/src/Slic3r/Biz/RemovableDrive/RemovableDriveServiceLinux.cpp b/src/slic3r-shared/src/Slic3r/Biz/RemovableDrive/RemovableDriveServiceLinux.cpp
index 3d9608f..f1eb1f9 100644
--- a/src/slic3r-shared/src/Slic3r/Biz/RemovableDrive/RemovableDriveServiceLinux.cpp
+++ b/src/slic3r-shared/src/Slic3r/Biz/RemovableDrive/RemovableDriveServiceLinux.cpp
@@ -4,7 +4,16 @@
 #include "Slic3r/Log.hpp"
 #include "Slic3r/Assert.hpp"
 #include <fmt/format.h>
+#include <boost/version.hpp>
+#if BOOST_VERSION >= 108800 // v2 is now default
+#define BOOST_PROCESS_VERSION 1
+#include <boost/process/v1/child.hpp>
+#include <boost/process/v1/io.hpp>
+#include <boost/process/v1/pipe.hpp>
+#include <boost/process/v1/search_path.hpp>
+#else
 #include <boost/process.hpp>
+#endif
 
 namespace Slic3r::Biz::RemovableDrive {