Add Tilt back from holos server
Note with this patch the ec-creds.yaml file needs to be applied to the
provisioner and an external secret used to sync the image pull creds.
With this patch the dev instance is accessible behind the auth proxy.
pgAdmin also works from the Tilt UI.
https://jeff.holos.dev.k2.ois.run/app/start
Remove the server.Config struct, not needed. Remove the app struct and
move the configuration to the main holos.Config.ServerConfig.
Add flags specific to server configuration.
With this patch logging is simplified. Subcommands have a handle on the
top level holos.Config and can get a fully configured logger from
cfg.Logger() after flag parsing happens.
Disambiguate the term `core` which should mean the core domain. The app
is a supporting domain concerned with logging and configuration
initialization early in the life cycle.
