feat(fractional): Redemption queue with FIFO ordering

[nanaf6203-bit]

Implement a transparent first-in-first-out redemption queue so fractional owners can request exit at NAV. Reference contracts/fractional/src/lib.rs.

[Hallab7]

@Hallab7 has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

I would like to work on this issue

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[DevMuhdishaq]

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

Hi Maintainer,

I’m a full-stack developer, and I’d like to contribute to the task. I’ll implement it carefully and efficiently thoroughly understand requirements and edge cases
Communicate promptly about suggestions or improvements. And I will provide regular progress updates and address blockers
Align with project goals through feedback and clarification.

Thank you,

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[code-0-stella]

@code-0-stella has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

Hello, I have reviewed the issue and understand what needs to be done.

I would appreciate being assigned to it.

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[drips-wave]

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

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