Implement initial configuration flow / registration
If the site has not been pre-configured (e.g., by a seamless installer like Hallo.gent), the site owner is presented with the Settings screen, with a Set Password modal over it.
Once the person has chosen a password, we:
- Create a private and public key
- We encrypt the private key with the password
- We store the public key and the encrypted private key on the server and get a JWT token via publickey authentication and set the person as signed in (see #19)
- Remove the modal and lead the person to set up their site from the Settings screen.