@Jake Kryten Thanks for asking question! Yes, its correct! There isn’t a customer facing feature in App Service to scan content such as uploaded files at this point.
There is already a feedback request created on Antimalware feature on Web Apps (App Service) you may upvote it. The product group monitors this site for feedback. This is the best way to ensure you are heard and you may receive a response depending on how much they information they can currently share. Having said that I will work with team Internally on this and keep you posted here.