Reworked event hook to a system with pre-allocated memory, owned by the battle. This deals with cleaning up event data memory.

src/Battling/Models/Battle.cpp

@@ -163,4 +163,4 @@ void Battle::AddVolatileScript(const ArbUt::StringView& key) {
 }
 void Battle::AddVolatileScript(Script* script) { return _volatile.Add(script); }
 void Battle::RemoveVolatileScript(Script* script) { _volatile.Remove(script->GetName()); }
-void Battle::DisplayText(const ArbUt::StringView& text) const { TriggerEventListener(new DisplayTextEvent(text)); }
+void Battle::DisplayText(const ArbUt::StringView& text) { TriggerEventListener<DisplayTextEvent>(text); }