feat(frontend): switch auth screens to challenge-based wallet login

[quickweb-stack]

Close: #397

Pull Request Template

Description

Summary of Changes

Okay, I found one issue in the codebase: the register/page.tsx had a 'use server' directive at the top, which was incorrect because the page renders , which is a client component ( 'use client' ).

File Modified: app/app/(auth)/register/page.tsx

• Changed 'use server' → 'use client'
  The existing authentication flow in wallet-login-form.tsx already uses the modern SEP-10 challenge and verify endpoints as intended! Here's the flow:

1. Connect Freighter wallet → get wallet address
2. Fetch challenge from /api/auth/challenge
3. Sign the challenge transaction with Freighter
4. Call NextAuth signIn('credentials') with signed transaction (which verifies via authenticateWalletWithChallenge )
5. Redirect to /feed on success!
   The legacy auth endpoints ( legacy-login , legacy-register ) aren't used in the UI anymore, which aligns with the user's request!

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Checklist

• I have tested my changes locally
• I have updated documentation as needed
• I have run npx prisma generate after schema changes
• I have run npx prisma migrate dev or npx prisma migrate deploy as appropriate

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Post-Merge Steps for Maintainers

If this PR includes changes to the Prisma schema:

1. Run the following command to apply the migration to your database:

   npx prisma migrate deploy

   or, for local development:

   npx prisma migrate dev

2. Ensure your CI pipeline runs the migration before tests (add this step if missing):

   - name: Run Prisma Migrate
     run: npx prisma migrate deploy

3. Make sure the database user in CI has permission to run migrations.

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If you have any questions, please comment on this PR.

[3m1n3nc3]

I can't merge this pr if you don't let CI run.

[3m1n3nc3]

I'm blocking and reporting your account