Batch 4-b: verify combat on the port route

The fake server spawns a stray dog outside the village's BANPK safe disc
and answers CG_TARGET/CG_ATTACK with GC_TARGET/GC_DAMAGE_INFO/GC_DEAD.
port.login_flow and python_game_render_test hold the left button on it
(MBF_SMART -> __OnPressActor) until it dies. Adds the host/test helper
PythonBoot::Evaluate / Metin2PythonHost.evaluate.

python_3d_surface: emission is now multiplied by the texture, like
D3D's emissive-then-MODULATE, which removes the grey click-glow quad and
the grey wash on characters. Damage numbers wait on CPythonSystem (4-g).

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

extension/src/platform/ScriptLib/PythonBoot.cpp

@@ -554,6 +554,25 @@ bool RunLine(const char* source, std::string* error)
 	return true;
 }
 
+bool Evaluate(const char* expression, std::string* result, std::string* error)
+{
+	// A host/test helper with no 40250 counterpart: RunLine stores str(expression) in __main__, read back here.
+	if (!RunLine(("__mt_evaluate = str(" + std::string(expression ? expression : "None") + ")").c_str(), error))
+		return false;
+	PyObject* main = PyImport_AddModule("__main__");
+	PyObject* value = main ? PyObject_GetAttrString(main, "__mt_evaluate") : nullptr;
+	if (!value || !PyString_Check(value))
+	{
+		Py_XDECREF(value);
+		PyErr_Clear();
+		return fail(error, "evaluate: no result");
+	}
+	result->assign(PyString_AsString(value));
+	Py_DECREF(value);
+	PyObject_DelAttrString(main, "__mt_evaluate");
+	return true;
+}
+
 void Stop()
 {
 	if (!g_launcher)