feat: direct join-us button to a new page. Install react hook form.

[TheSKBroook]

Pull Request Summary

Title

Create a Join-us Page and a registration-form components, while adding validation and test.

Overview

This branch focuses on the registration form used for the "Join Us" flow. It improves how the form reacts to university selection changes, tightens validation, connects the form to Supabase correctly, and adds test coverage for the major behaviors.

What Changed

Form behavior

• Made the university-dependent fields react properly when the university changes ( see below )

- Clear hidden fields back to `null` when the user switches university type.

Validation

• Add form schema and Enums ( Degree, Year, University )
• Added user-friendly validation messages for required fields.
• Ensured UOA, AUT, and Other university paths require the correct fields.
  • example: Selecting Other in University field cannot have University_Other to be null.

Supabase integration

• Connected the email-exists check to the is_email_registered RPC function.
  • I made a Remote Procedure Call in supabase so that the check is done my database side, preventing public user accessed the entire email list.
• Create a server folder and kept registration submission routed through the RegistrationService.

Tests

• Added and updated Vitest / Testing Library coverage for:
  • initial render
  • university-specific conditional fields
  • numeric-only Student ID input
  • clearing fields when changing university
  • validation on missing inputs
  • email taken / email available submission flows

Testing

• bun vitest run src/components/test/registration-form.test.tsx

Improvement for later

• Increase Scalability by using tanstack query
• Create a successful submission page or customize the alert

Relevant Files

• src/app/pages/join-us/page.tsx
• src/components/registration-form.tsx
• src/components/test/registration-form.test.tsx
• src/lib/schemas/registration.ts
• src/services/registrations/registrations-service.tsx

Some Images

[rebeccafitzpatr]

I like the dynamic change when selecting different uni !!
However, the Id field is an integer and has increment arrows -- not suitable . Potential fix: switch this out for plain string entry field and limit input to just characters ( 0-9 )

Also add text input field for 'Other' Faculty