Adding SvelteKit Auth/Auth.js to the main stack

[L-Mario564]

Implementing Vercel's official auth solution for SvelteKit.

Checklist

• Auth.js (as a standalone package)
• Auth.js + Prisma
• Auth.js + Prisma + tRPC
• Update README with information about this package

[zach-hopkins]

Great thanks on all this @L-Mario564! Much appreciated. Looks good to me on a glance, i'll give it a thorough review later. What's left on the tRPC + Auth + Prisma front?

[L-Mario564]

With tRPC, I seem to have issues, iirc it's related to types. Other than that I have to update a few things since a few breaking changes were introduced in the auth package (as well as waiting for a few issues to be solved for it)

[m9p909]

the create-t3-app starter has commented out db.text fields. These comments will save the users a lot of headache when they see the string too long SQL error.

    providerAccountId String
    refresh_token     String? // @db.Text
    access_token      String? // @db.Text
    expires_at        Int?
    token_type        String?
    scope             String?
    id_token          String? // @db.Text