To be fair, all you’d need to accomplish that without more than necessary parts for production is to ensure that the code path invoking the function is accessed

To be fair, all you’d need to accomplish that without more than necessary parts for production is to ensure that the code path invoking the function is accessed via an external monitoring probe with an adjustment to SLA or SLO to account for the cold start time. Obviously not going to work for many systems, but it’s easy to forget all the side effects of the observability plane when writing applications.