Reject create_vault when a milestone due_date is in the past in accountability_vault

[1nonlypiece]

Reject create_vault when a milestone due_date is in the past in accountability_vault

Description

create_vault in contracts/accountability_vault/src/lib.rs validates that end_timestamp is in the future and that each milestone.due_date <= end_timestamp, but does not reject a milestone whose due_date is already in the past relative to env.ledger().timestamp(). Such a milestone can never be checked in, guaranteeing a slash. Add the lower-bound validation and a failing-case test.

Requirements and context

• Must be secure, tested, and documented
• Should be efficient and easy to review
• Add due_date > env.ledger().timestamp() validation in create_vault
• Return the existing InvalidDeadline error code in contracts/accountability_vault/src/lib.rs
• Add a past-due-date rejection test in contracts/accountability_vault/src/test.rs
• Note the rule in contracts/README.md

Suggested execution

• Fork the repo and create a branch
• git checkout -b bug/reject-past-due-milestone
• Implement changes
  • Modify contracts/accountability_vault/src/lib.rs
  • Add a test in contracts/accountability_vault/src/test.rs
  • Update contracts/README.md
  • Add boundary comments
• Test and commit
  • Run tests, cover edge cases
  • Include test output and notes

Example commit message

fix: reject past milestone due dates in create_vault

Guidelines

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

[drips-wave]

Congratulations, @Dev-Mat852! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 2, 2026.

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