Add documentation/config for auth0 constants #131
Description
When starting the local stack for the first time, the app immediately redirects to https://undefined/authorize, making login impossible. This is because the Vite dev server builds Auth0 config from VITE_AUTH0_* environment variables, which is not bundled with setup currently.
gitignored and was never generated by start_local.sh, so import.meta.env.VITE_AUTH0_DOMAIN (and siblings) are undefined at runtime.
To onboard new peiple, we should either ship (currently gitignore'ed) app/frontend/.env.local with the Auth0 credentials or document this somewhere and perhaps integrate this into our scripts.
Required vars:
VITE_AUTH0_DOMAIN=...
VITE_AUTH0_CLIENT_ID=...
VITE_AUTH0_AUDIENCE=...
VITE_AUTH0_ORGANIZATION_ID=...