Proper typing for $page.data.session just like $session?

[AaronFlynn1989]

Describe the problem

I feel like I'm missing something obvious. $session was removed in #5946 and the alternative proposed in #5883 is using layout load functions and retrieving the session info there and then returning it as part of the data; which I am doing, but I'm not sure how I should have proper typing for $page.data.session?! Previously I was declared the type of the session object in app.d.ts's App.Session, and then just used the typed $session store everywhere, which was very convenient, I'm confused as to how I'm supposed to achieve something similar now?!

Describe the proposed solution

I don't know, really

Alternatives considered

No response

Importance

i cannot use SvelteKit without it

Additional Information

No response

[elliott-with-the-longest-name-on-github]

Closing as a duplicate of #5951. Read through the discussion there -- Rich is working on implementing this! :)