Port PythonExceptionSender and install it at boot as 40250 Main does

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/platform/ScriptLib/PythonBoot.cpp

@@ -14,6 +14,7 @@
 #include "../EterLib/HostCursor.h"
 #include "UserInterface/PythonNetworkStream.h"
 #include "UserInterface/AccountConnector.h"
+#include "UserInterface/PythonExceptionSender.h"
 #include "UserInterface/ServerStateChecker.h"
 #include "UserInterface/PythonPlayer.h"
 #include "GameLib/FlyingObjectManager.h"
@@ -70,6 +71,8 @@ namespace
 {
 // 40250 has this on Main()'s stack. CPythonLauncher is a CSingleton, so there is still only ever one.
 std::unique_ptr<CPythonLauncher> g_launcher;
+// 40250 Main(): CPythonExceptionSender pyExceptionSender; SetExceptionSender(&pyExceptionSender);
+std::unique_ptr<CPythonExceptionSender> g_exception_sender;
 std::unique_ptr<UI::CWindowManager> g_window_manager;
 std::unique_ptr<CPythonResource> g_resource;
 // 40250 CPythonApplication::m_timer; CSlotWindow's cool time and Process() read it via Instance().
@@ -733,6 +736,8 @@ bool Start(const char* stdlib_path, std::string* error)
 	PythonHost::Configure();
 
 	g_launcher = std::make_unique<CPythonLauncher>(); // Py_Initialize
+	g_exception_sender = std::make_unique<CPythonExceptionSender>();
+	SetExceptionSender(g_exception_sender.get());
 	// The script fiber (RunMainScript) is a second OS thread; 2.7 creates the GIL lazily.
 	PyEval_InitThreads();
 	if (!g_launcher->Create())
@@ -1071,6 +1076,9 @@ void Stop()
 	g_window_manager.reset();
 	g_resource.reset();
 	g_timer.reset();
+	// PORT: 40250 leaves g_pkExceptionSender dangling once Main() returns; Boot can run again here.
+	SetExceptionSender(NULL);
+	g_exception_sender.reset();
 	g_launcher.reset();
 }