Implement On-Chain Role Delegation with Expiration (Time-Bound Roles)

[thlpkee20-wq]

Description
Extend access control roles to support time-bound delegation (e.g., grant Reporter role to an address until a given period end or timestamp).

Requirements and context

• Must allow granting roles with an expiration (e.g., block height, ledger sequence, or logical period).
• Must ensure expired roles are treated as inactive in all auth checks.
• Must emit events when roles are granted, renewed, or naturally expire (if possible).

Suggested execution

• Branch: git checkout -b feature/time-bound-role-delegation.
• Extend role storage to include an expiration field; design how time/period is measured (e.g., period_id, block timestamp if available).
• Update auth checks to reject expired roles.
• Add methods to renew or revoke roles explicitly.
• Add tests in src/test.rs to verify expiration and renewal behavior, including boundary conditions.

Test and commit

• Run cargo test.
• Cover edge cases: role granted without expiration, expiration at current period, expired role used after threshold.
• Include test output and document how off-chain systems should reason about role expiry.

Example commit message
feat(contracts): add time-bound role delegation for offerings

Guidelines

• Minimum 95 percent test coverage.
• Clear documentation about the time/period source used for role expiry.
• Timeframe: 96 hours.

[Baskarayelu]

I’d love to be assigned this issue and contribute across the relevant areas, whether it involves smart contracts, UI development, backend logic, design implementation, or overall system integration. I’m comfortable working across the full stack and can adapt to the project’s technical requirements to ensure a smooth and consistent contribution.