Running the `memgpt server` with "authless" mode

[cpacker]

For users that plan to use the server and/or dev portal as a single user, there should be a way to run memgpt server in an "authless" mode that:

1. disables the requirement to log into the dev portal (it logs you in as the admin by default)
2. disables the requirement to use bearer tokens on API calls (uses admin user by default)