iframe - Connect to backend api and implement business logic

[hkd987]

After completion of #1 & #2 we should be ready to wire up the business logic for our iframe.

This issue if not already completed by #2 could also include putting a publishing and design system in place but might not. This ticket should allow the iframe to load quickly and will need the following logic

• Login users, users
• Register users, users
• Display "Powered By Authsio" link for unpaid accounts
• Remove "Powered By Authsio" for paid accounts
• Should read the users public api key for this information
• Should handle basic email validation rules, maybe HTML5 email validation is enough
• Should handle basic password validation rules, maybe HTML5 password validation is enough
• Should score over 90% on lighthouse across the board. We do not want to slow down users websites

IF YOU PLAN TO CONTRIBUTE OR WORK ON THIS ISSUE, LETS CHAT FIRST TO SYNC UP.