Add a paginated read view enumerating only the currently revoked attestation digests

[mikewheeleer]

Add a paginated read view enumerating only the currently revoked attestation digests

Description

The append-log exposes get_attestation_append_log, get_attestation_digest_at, and is_attestation_revoked. To list which digests are currently revoked, an integrator must read the whole log, then probe is_attestation_revoked for every index — O(N) round-trips and no way to page. There is a paginated view of revoked indices already, but none returning the digests themselves in revoked state.

This issue adds get_revoked_attestation_digests(start, limit) -> Vec<AttestationDigestInfo> that pages over the log and returns only entries whose index is currently revoked, so an auditor can fetch revoked digests directly.

Requirements and context

• Repository scope: Liquifact/Liquifact-contracts only.
• Add get_revoked_attestation_digests(start: u32, limit: u32) -> Vec<AttestationDigestInfo> reusing the same AttestationDigestInfo shape returned by get_attestation_digest_at.
• Page over the append-log honoring start/limit, and skip indices that are not currently revoked (respecting any prior unrevoke_attestation_digest).
• Bound limit with the existing pagination ceiling; return an empty Vec past the end rather than panicking.
• Pure read-only: no auth, no writes, no TTL bump.

Suggested execution

• Fork the repo and create a branch
• git checkout -b feature/contracts-revoked-digests-view
• Implement changes
  • Write code in: escrow/src/lib.rs — get_revoked_attestation_digests.
  • Write comprehensive tests in: escrow/src/tests/attestations.rs — assert only revoked entries appear, pagination boundaries, exclusion of un-revoked entries, empty result past the end, and the over-cap guard.
  • Add documentation: extend the attestation docs and integrator view-surface reference.
  • Include NatSpec-style doc comments (///) on the new view.
  • Validate security assumptions: bounded reads, no mutation, correct interaction with un-revoke.
• Test and commit

Test and commit

• Run cargo fmt --all -- --check, cargo build, and cargo test.
• Cover edge cases and failure paths: no revocations, mixed revoked/un-revoked, page past end, limit above the cap.
• Include the full cargo test output and a short security notes section in the PR description.

Example commit message

feat: add paginated revoked-attestation-digests read view with boundary tests

Guidelines

• Minimum 95 percent test coverage for impacted modules.
• Clear, reviewer-focused documentation.
• Timeframe: 96 hours.

Community & contribution rewards

• 💬 Join the Liquifact community on Discord for questions, reviews, and faster merges: https://discord.gg/JrGPH4V3
• ⭐ This is a GrantFox OSS / Official Campaign task and may be rewarded. When your PR is merged you'll be prompted to rate the project — if this issue and the maintainers helped you ship, we'd be grateful for a 5-star rating. Clear questions in Discord and tidy, well-tested PRs are the fastest path to a merge and a reward.

[nanaabdul1172]

Hello,

I'd like to take on this issue. I can implement the required contract changes using Rust and the Soroban SDK, following existing project patterns and best practices.

I'll include comprehensive tests, validate expected behavior and failure cases, and ensure the contract compiles cleanly and passes all project checks.