Add migration checksum verification on startup

[Chucks1093]

Summary
Add migration checksum verification on startup

Scope

• verify expected migration checksums at startup\n- fail fast on detected drift\n- provide actionable operator error output

Acceptance Criteria

• scoped change is implemented with no unrelated file churn
• docs/tests are updated where applicable
• contributor can validate the outcome locally

Contributor coordination: if you pick this up, reach out in Telegram for updates or clarification: https://t.me/accesslayerorg

[Benalex8797]

@Benalex8797 has applied to work on this issue as part of the Stellar Wave Program's 4th wave.

i will like to work on this issue

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Benalex8797 to this issue.

[drips-wave]

Congratulations, @Benalex8797! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on April 29, 2026.

🧑‍💻 @Benalex8797: 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 🌊

[drips-wave]

This issue has been completed by @Benalex8797 as part of the Stellar Wave Program's 4th Wave 🥳

😎 @Benalex8797: You earned 200 Points for completing this issue! After the current Wave ends, you'll be eligible for a percentage of the Wave's reward pool based on the percentage of total points you've earned. Learn more here. You can also Leave a review to share your experience working on this issue.

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