Try and catch more edge cases where setIndex would be invalid.

Signed-off-by: Deukhoofd <Deukhoofd@gmail.com>

src/Battling/ScriptHandling/ScriptAggregator.hpp

@@ -25,6 +25,9 @@ namespace CreatureLib::Battling {
                 _index++;
             while (HasNext()) {
                 if (_scripts[_index].HasValue()) {
+                    if (_scripts[_index].IsSet()) {
+                        _setIndex = -1;
+                    }
                     return;
                 }
                 _index++;