Landing page for users with no orgs

[sinabahram]

After we deleted a bunch of orgs from staging, users that had no remaining organizations now get a 404 on login, which makes sense, but we need somewhere for those users to land, especially so that they may create an org if desired.

[jkva]

Linking https://sentry.io/organizations/coyote-org/issues/2976201165/?environment=staging&project=5201913&referrer=alert_email here since I suspect the error has to do with no organizations being available after login.