Haha Steve... Not owing the glasses but always eager to help :)
There is no Store in the Meta AI-App but you're right in the app there is the "app connection" option where you can connect music and health and so on. Calendar is not shown to me as well (but I've heard of some US users having it).
Maybe I have to get more achievements to unlock it or ask Meta AI friendly for it xD
And strangely: when I follow the link you've posted with the app connections via the horizon account, I can't see any app connections I have made in the Meta AI-App and I am also unable to establish new connections since no apps are shown there to connect. Probably that's the connection for the vr headset only.
Anyways: have a nice day Steve!