[Frontend] — Finalize event & claim prize flow + `PrizePoolSummary`

[Olowodarey]

Background

There is currently no UI anywhere that shows the prize pool, reward
distribution, a "Finalize Event" action, or a "Claim Prize"
action. [id]/page.tsx's action bar (lines 273-343) only has Join, Make
Predictions, Add Match, Cancel Event, and (soon-removed) Verify Winners.

Goal

Add a PrizePoolSummary component showing the prize pool + reward split,
and wire up "Finalize Event" (visible once endsAt has passed and not yet
finalized) and "Claim Prize" (visible to a user with an unclaimed payout on
a finalized event) actions using Issue 1's finalizeEvent/claimPayout/
getUserPayout.

Acceptance Criteria

• PrizePoolSummary renders prize pool, reward breakdown (with XLM
• "Finalize Event" button appears only when `!isFinalized &&
• Clicking "Finalize Event" calls finalizeEvent, then the page reflects
• On a finalized event where the connected wallet has an unclaimed
• A user with no payout on a finalized event sees neither claim button

[VinolNoronha]

Hi, I'd like to work on this. Is it currently unassigned? I'm familiar with Next.js and Tailwind and happy to submit a PR targeting develop

[Johnpii1]

Hello Sir,

I came across your project and I’m really interested in contributing.

I have experience with React for building responsive, user-friendly interfaces, and I’m also familiar with smart contracts and blockchain basics. I focus on writing clean, scalable code and improving user experience.

I’m a fast learner and ready to get started immediately. Please let me know the next steps.

Thank you.

Best regards,
Johnpaul

[grantfox-oss]

🦊 GrantFox — @Johnpii1 has been assigned to this issue as part of the Official Campaign campaign!

Next steps:

1. Open a Pull Request referencing this issue (e.g., Closes #950)
2. Your PR will be reviewed by the Arena1X maintainers

Good luck! Track your progress on GrantFox.

[grantfox-oss]

🎉 This issue has been marked as completed on GrantFox as part of the Official Campaign campaign!

@Johnpii1's PR #985 was approved and merged by @Olowodarey.

🏆 @Johnpii1: You earned 35 FoxPoints for this contribution! Your current tier: Explorer (293 total points). Track your full progress on GrantFox.

👏 Great work, @Johnpii1! Keep contributing to Arena1X.