RFC for Magic sign-in link via email

Summary Add a "Magic sign-in link" option to the available authentication methods. Users must be able to choose a Magic sign-in option in addition to any other enabled option to sign in. This authentication method should work for both the Directus app and authentication through API. This authentication should be an extension of default (database) authentication. That is, the auth method on the account will be "default". As a result only accounts with a "default" authentication method will be able to use Magic link auth, although it may change in the future when/if authentication by any method (regardless of what method was used to create an account) is supported by Directus. Basic Example Example 1 1. User opens the Directus app, enters email and clicks on "Send me a magic link" link/button 2. Directus generates a magic link and emails it to the user. 3. User clicks on the link in the email that authenticates them and redirects back …