intro-component-with-signup-form

Originally, I was going to write this where Spring Boot served some of the components' content, and the form would be validated by Spring Boot. However, I abandoned this idea because Heroku isn't free and requires a credit card, which I don't feel comfortable with. However, Next.js 13's latest experimental feature, 'server actions,' makes writing forms much easier if anyone wants to look into it (https://nextjs.org/docs/app/building-your-application/data-fetching/server-actions). I tried to write decent regex, which most likely failed in some sense. I'm pretty sure there is a tricky bug between my state updates and regex checking that will trigger the redirect to a simple success page. Also worth checking the type definition of action attribute.