fix ReadSocketWithTimeout to use dedicated io context polled on a new jthread

jthread so it's cancellable

include/TNetwork.h

@@ -28,6 +28,19 @@
 
 struct TConnection;
 
+class TIoPollThread {
+public:
+    TIoPollThread();
+    ~TIoPollThread();
+
+    boost::asio::io_context& IoCtx() noexcept { return mIoCtx; }
+
+private:
+    boost::asio::io_context mIoCtx;
+    boost::asio::executor_work_guard<boost::asio::io_context::executor_type> mWorkGuard;
+    std::jthread mThread;
+};
+
 class TNetwork {
 public:
     TNetwork(TServer& Server, TPPSMonitor& PPSMonitor, TResourceManager& ResourceManager);
@@ -63,6 +76,7 @@ private:
     std::thread mUDPThread;
     std::thread mTCPThread;
     std::mutex mOpenIDMutex;
+    TIoPollThread mIoCtxPoller;
     TConnectionLimiter mConnectionLimiter;
 
     std::vector<uint8_t> UDPRcvFromClient(boost::asio::ip::udp::endpoint& ClientEndpoint);