How can I validate the JWT from a purchase from StoreKit 2 using PHP? I can't find any example on the internet. The video say "Then use your favorite cryptographic library to verify the data with", but I don't know anything about that.

If I'm using StoreKit 2 and App Store Server Notifications v2, do I really need to implement Transaction.updates inside my app? My app has an auto-renewable subscriptions InApp Purchase and I don't want to have data race problems with the subscriptions status updates on my server.