[DOCS] [ops] Write the rollback rehearsal script

[determined-001]

Description
"Rollback rehearsed" is a manual gate in scripts/mainnet-preflight.mts and the runbook describes the concept without giving anyone a script to follow. An upgrade cannot be undone by re-running the deploy.
Requirements

• Write the step-by-step rehearsal against a testnet deployment.
• Record what was observed at each step so the real rehearsal has a baseline.

Acceptance Criteria

• Someone who has never deployed this contract can follow it.

Estimated File Changes: 2 (docs/MAINNET_LAUNCH.md, docs/ORACLE_MIGRATION.md)

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Filed from batch-readiness.md · R44

[DevALVIN-24]

@DevALVIN-24 has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

Hi, I'd like to work on this issue! because I am very conversant with solving problems like this, and i can submit the pr with 48hr

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[Hussman256]

@Hussman256 has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

Understanding of the task

"Rollback rehearsed" is currently a manual, unscripted gate in scripts/mainnet-preflight.mts — the runbook talks about the concept but gives no concrete steps, and since an upgrade can't be undone by just re-running the deploy, this needs an actual rollback procedure someone can execute and verify against a testnet deployment before it's ever needed on mainnet.

Proposed approach

Walk through an actual upgrade + rollback cycle against testnet myself first, so the doc reflects real observed behavior rather than assumed steps.
Write it as a literal step-by-step script in docs/MAINNET_LAUNCH.md (and cross-reference docs/ORACLE_MIGRATION.md where oracle-specific rollback steps differ), assuming no prior context — commands to run, what to check after each one, and what "this step succeeded" looks like concretely (not just "verify it worked").
Record the actual output/state observed at each step during my rehearsal, so it doubles as a baseline for comparison during the real rehearsal or an actual incident.
Call out anywhere the rollback path is not simply reversible (e.g. state migrations, oracle data), since those are the riskiest spots and the ones most likely to trip someone up.

Testing plan

Have someone unfamiliar with the deploy process (or simulate that by not relying on tribal knowledge) follow the doc against testnet and confirm they can complete it without asking me anything.
Confirm the documented steps match current scripts/mainnet-preflight.mts behavior, not a stale version of the deploy flow.

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[QwinDivy]

@QwinDivy has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

Maintainer, I’m happy to take this one. After reviewing the codebase, I’m comfortable with the proposed approach and ready to get started. I’ll keep the scope focused, add solid test coverage, and ensure CI stays green. I’d be glad to open a draft early so we can confirm the direction together.

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Congratulations, @QwinDivy! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on August 31, 2026.

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