...
  callbacks: {
    async signIn({ user, account, profile, email, credentials }) {
      return true
    },
    async redirect({ url, baseUrl }) {
      return baseUrl
    },
    async session({ session, user, token }) {
      return session
    },
    async jwt({ token, user, account, profile, isNewUser }) {
      return token
    }
...
}

const user = await prisma.user.findUnique({
  where: {
    email: 'elsa@prisma.io',
  },
})

select: {
    token: true
  },

session.token = token

return session