Throw error when simulation script can't be loaded

When a script in "simulation/helpers/" contained an error. Files in
"simulation/components" aren't loaded. The return value of
`LoadDefaultScripts` indicated an error but was ignored. The simulation
still tried to start.

Now instead of returning a ignoreable error code the error is thrown. In
the common path the error is implicitly rethrown to the JS-function
which tried to start the game.

fixes: #8133

source/tools/atlas/GameInterface/ActorViewer.cpp

@@ -320,7 +320,14 @@ ActorViewer::ActorViewer()
 	}
 
 	// Prepare the simulation
-	m.Simulation2.LoadDefaultScripts();
+	try
+	{
+		m.Simulation2.LoadDefaultScripts();
+	}
+	catch (const CSimulation2::LoadScriptError& e)
+	{
+		LOGERROR("%s", e.what());
+	}
 	m.Simulation2.ResetState();
 
 	// Set player data