[api] Use const char* pointers for light effects to eliminate heap allocations (#12090)

esphome/components/api/api_pb2_dump.cpp

@@ -924,7 +924,7 @@ void ListEntitiesLightResponse::dump_to(std::string &out) const {
   }
   dump_field(out, "min_mireds", this->min_mireds);
   dump_field(out, "max_mireds", this->max_mireds);
-  for (const auto &it : this->effects) {
+  for (const auto &it : *this->effects) {
     dump_field(out, "effects", it, 4);
   }
   dump_field(out, "disabled_by_default", this->disabled_by_default);