Adds getter for UniqueIdentifier

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

src/Library/CreatureData/CreatureSpecies.cpp

@@ -20,8 +20,10 @@ bool CreatureSpecies::TryGetVariant(uint32_t hash, ArbUt::BorrowedPtr<const Spec
 }
 
 void CreatureSpecies::SetVariant(const ArbUt::StringView& name, const SpeciesVariant* variant) {
+    Assert(!name.IsEmpty())
+    AssertNotNull(variant)
+    _variantsList.CreateBack(variant);
     _variantsLookup.GetStdMap().insert({name, std::unique_ptr<const SpeciesVariant>(variant)});
-    _variantsList.Append(variant);
 }
 
 Gender CreatureSpecies::GetRandomGender(ArbUt::Random& rand) const noexcept {