My VW app used to provide an overview of all dealer events. Was useful when buying used as it logged service and repair events dates so dealer could be 'interrogated'! Probably, one reason why it was discontinued and the fact that not all dealerships used it. I was fortunate that it was still in use when I bought my last golf. Almost as good as a set of invoices. Good luck getting the build sheet. Like getting blood from a stone probably.
The way the 'online service data' was sold to me by VW was that i can access it anywhere online via the VW website. After a few failed attempts to find it on the website and on the VW app i went back to them, only to be told it's only available to them online and i'd have to request it through them.
I've yet to find anything useful on the app, it shows my what's locked and i can unlock it, flash the indicators and sound the horn.....which i'm guessing may be handy if i've forgotten where i've parked, it's never happened in 32 years but you never know lol. I can request a vehicle health report that comes by email, may be handy so gave it a try, never got the email!
If you do want to see what options your car came with from factory and your dealership isn't playing ball with giving you an official build sheet. There maybe another option if you don't mind spending about £10 for 24 hours' access.
I've used the partslink24.com website to view exploded component diagrams and find part numbers for various bits for my GTI. You can buy parts through this too, but I never have; just used it to get part numbers and indication of prices. One of the features the website did have, and I assume still does, was where you put in your car's VIN and it'll show what was included at the factory. Basically deciphering all the PR numbers.
I had a quick nosy at partslink24 but couldn't see anything that immediately jumps out as a vehicle build, i did see this "Distinct parts identification via VIN input" but wasn't prepared to pay £10 to find out if it's the bit i'm after, that may change after i've been to VW on Tuesday though.