Session redo

[markphelps]

Slight session refactor:

• remove unneccessary info from session data
• renamed flipt to session since its used by the SessionProvider
• added two fields required and authenticated to make logic of if auth is required and if user is logged in simpler
• base64 encode session value
• merged in changes from fix: clear session on logout #60

With Auth

Base64 decoded:

{"authenticated":true,"required":true,"self":{"id":"8c4a8613-ee9b-473f-919c-801455400365","method":"METHOD_OIDC","expiresAt":"2023-02-02T15:28:18.436540Z","createdAt":"2023-02-01T15:28:18.436542Z","updatedAt":"2023-02-01T15:28:18.436542Z","metadata":{"io.flipt.auth.oidc.email":"mark@flipt.io","io.flipt.auth.oidc.email_verified":"true","io.flipt.auth.oidc.name":"Mark Phelps","io.flipt.auth.oidc.picture":"https://lh3.googleusercontent.com/a/AEdFTp6IhGYsbE2F8Y3xsvrfOg_zYSNjWi04GiydVs1m=s96-c","io.flipt.auth.oidc.provider":"auth0"}}}

Without Auth

Base64 decoded:

{"authenticated":false,"required":false}

[darinmclain]

LGTM!