Add holder lockup periods preventing transfer and redemption until lockup_end

[thlpkee20-wq]

Description

Some offerings impose a holder-level lockup (e.g. 12 months from purchase). Add set_holder_lockup(offering_id, holder, lockup_end_ts) enforced by transfer and redemption paths, with structured-error rejection prior to lockup_end.

Requirements and context

• Must be secure, tested, and documented
• Should be efficient and easy to review
• Relevant code: Revora-Contracts/src/lib.rs
• Claim of accrued revenue must remain allowed during lockup; only share movement is gated

Suggested execution

• Fork the repo and create a branch
• git checkout -b feat/holder-lockup-periods
• Implement changes
  • Add Lockups storage map keyed by (offering_id, holder)
  • Gate transfer_with_attestation and request_redemption on now >= lockup_end
  • Emit lockup_set and lockup_block events
• Validate security and correctness assumptions

Test and commit

• Run tests
  • cargo test --all
• Cover edge cases
  • lockup_end == now must permit the action
• Include test output and security notes

Example commit message

feat: enforce holder lockup periods on transfer and redemption

Guidelines

• Minimum 95 percent test coverage
• Clear documentation
• Timeframe: 96 hours

[Abdulmajeed82]

@Abdulmajeed82 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 pls...

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[drips-wave]

Congratulations, @Abdulmajeed82! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 30, 2026.

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