Add Escrow Balance Queries with Historical Snapshots

[famvilianity-eng]

Add Escrow Balance Queries with Historical Snapshots

Priority: Low
Estimated Time: 2 hours

Description

There is no way to query historical escrow balances for a player. Analytics and reporting require snapshotting balance at key points.

Tasks

• Add DataKey::PlayerBalanceSnapshot(player, u64) to store balance history
• Implement get_balance_at_timestamp(env, player, timestamp) -> i128
• Record snapshot on every deposit, withdrawal, and payout
• Add tests for snapshot accuracy across multiple operations

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Auto-created from UNSOLVED_ISSUES_40.md

[Osifowora]

@Osifowora has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

​Hi maintainer, I would love to work on this issue. I can get started on it right away.

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

[drips-wave]

Congratulations, @Osifowora! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 30, 2026.

🧑‍💻 @Osifowora: 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 🌊

[grantfox-oss]

🦊 GrantFox — @Osifowora has been assigned to this issue!

Next steps:

1. Open a Pull Request referencing this issue (e.g., Closes #953)
2. Your PR will be reviewed by the StellarCheckMate maintainers

Good luck! Track your progress on GrantFox.

[grantfox-oss]

🎉 This issue has been marked as completed on GrantFox!

@Osifowora's PR #1015 was approved and merged by @famvilianity-eng.

🏆 @Osifowora: You earned 35 FoxPoints for this contribution! Your current tier: Explorer (541 total points). Track your full progress on GrantFox.

👏 Great work, @Osifowora! Keep contributing to StellarCheckMate.