[Backend] Sync wallet balance and transaction history from chain

[Kaylahray]

Description

The wallet balance endpoint still falls back to local ledger data and a placeholder XLM asset snapshot instead of reconciling with live chain state.

User Story

As a wallet user,
I want to see my real balances and transfer history,
so that the wallet page matches the ledger.

Requirements and Context

• Files: app/app/api/wallet/balance/route.ts, app/app/api/wallet/transactions/route.ts, app/lib/prisma.ts
• Pull live asset balances from Stellar when non-simulated mode is used
• Reconcile local wallet history with on-chain transfer records
• Return consistent balance, asset, and transaction payloads to the frontend

Suggested Implementation

// BALANCE AND TRANSACTIONS
// 1. Load chain balances for the wallet address.
// 2. Merge live chain state with local transaction history.
// 3. Return the normalized payload to the client.
// 4. Keep simulated mode as a fallback only.

Acceptance Criteria

• Live balances are returned when the app requests non-simulated data.
• Transaction history reflects the wallet's real transfer activity.
• The response schema remains stable for the frontend.

Submission Guidelines

• Branch: feat/wallet-sync
• Depends on: Stellar read utilities and wallet address lookup
• PR: feat(backend): sync wallet balances and transaction history from chain

[morapay-app]

@morapay-app has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

I’d like to work on this issue because it fixes a core reliability gap between the wallet UI and real on-chain state. I can integrate live balance fetching from Stellar, reconcile it with local transaction records, and ensure the API returns a consistent, frontend-stable payload while keeping simulated mode as a fallback.

ℹ️ Repo Maintainers: To accept this application, review their application or assign @morapay-app to this issue.

[phertyameen]

@phertyameen has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

Hi, I will like to work on this issue.
I have an eta of 12 hrs

ℹ️ Repo Maintainers: To accept this application, review their application or assign @phertyameen to this issue.

[drips-wave]

Congratulations, @phertyameen! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 2, 2026.

🧑‍💻 @phertyameen: Please resolve the issue such that the repo's maintainers have enough time to review your contribution before the due date. You'll earn Points for completing the issue on-time, which will make you eligible for a share of the Stellar Wave Program's reward pool.

Warning

When opening a PR, please link it to this issue to ensure it gets tracked accurately. Points are awarded when this issue is marked as completed by the maintainer.

🤠 Repo maintainers: Please keep an eye on the contributor's progress and review their work before the due date. You can manage this issue, including adjusting its complexity and points, here.

🌊 Happy Wave 🌊