Out-of-order + skipped-message key handling

[codebestia]

Handle Signal's skipped message keys / out-of-order delivery (network reordering, multi-device). Bound stored skipped keys to prevent unbounded growth. Verify against the library's test vectors.

Acceptance criteria:

• Out-of-order messages decrypt correctly
• Skipped-key storage is bounded
• Library test vectors pass

[temieehade-coder]

@temieehade-coder has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

Hello maintainer, I can fix this issue

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[abdulwahabmonilola-ctrl]

@abdulwahabmonilola-ctrl has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

I’ve carefully reviewed the requirements and will implement a robust solution that aligns with the project standI’ve carefully reviewed the requirements and will implement a robust solution that aligns with the project standards and meets all acceptance criteria.

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[Ssoleed]

@Ssoleed has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

hi maintainer. i would like to work on this issue please.

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[ndyugwu]

@ndyugwu has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

i would like to work on this

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[onakijames-droid]

@onakijames-droid has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

I would like to work on this issue and submit a PR for it please assign it to me

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[devchant]

@devchant has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

Hey, can I solve this? I intend to understand the current code flow first, then develop a clean and scalable implementation that adheres to the project's conventions. I'll also verify the implementation with appropriate tests before submitting my work.

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[drips-wave]

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

🧑‍💻 @devchant: 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.

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