Add a special unauthenticated route for demo on dev and staging

[nid90]

Why

Have a public demo page for sales and marketing purposes where we don't have to create external viewer credentials

This addresses

• Allows one organization on staging environment to be selected as "demo organization" and all the data for the organization will be public (available without requiring login) on <staging-url>/demo.
• Updates anonymize script to allow multiple apps to be anonymized at the same time
• Adds new columns in anonymize script

The following setup is required beforehand:

org = Accounts::Organization.create!(status: "active", name: "Demo org name", created_by: "[email protected]")
demo_email = "[email protected]"
email_authentication = Accounts::EmailAuthentication.find_or_initialize_by(email: demo_email)
demo_user = Accounts::User.find_or_create_by!(full_name: "Demo User", preferred_name: "Demo User", admin: false, unique_authn_id: demo_email)
email_authentication.update!(password: <some password>, confirmed_at: DateTime.now, user: demo_user)
org.memberships << Accounts::Membership.new(user: demo_user, organization: org, role: "viewer")

Also, requires the following env variables:

DEMO_ORG_SLUG=<demo-org-slug>
DEMO_USER_SLUG=<demo-user-slug>

Additionally, a flipper flag must be enabled for the demo organization - demo_mode.