Beta Channel Typescript Docs

[michaelcmelton]

@lluia @balazsorban44 Are there Typescript Docs for the WIP migration on the beta channel from @types/next-auth that will need to be worked on? There's a pain point that I've found when working with .env files that may be entirely my lack of knowledge, or you may want included in the docs. I thought it would be best for me to ask here before blatantly opening an issue and a PR. Thanks for your time in advance.