feat: WIP-106 tokens generation & circuits

[paolodamico]

Note

Medium Risk
New cryptographic token formats and in-circuit signature/CBOR verification are security-sensitive, though largely additive/WIP with extensive KAT coverage and no change to embedded ownership-proof artifacts yet.

Overview
Adds WIP-106 authenticator attestation end-to-end: Rust helpers to mint Trust Anchor Key Tokens (BabyJubJub EdDSA over a Poseidon2 claim digest) and Authenticator Assertion Tokens (ES256 over COSE Sig_structure, with the TAKT embedded under submods.takt), plus a new Noir authenticator-assertion library that checks the same chain in-circuit (verify_takt, verify_aat).

The Noir side rebuilds deterministic CBOR at fixed offsets (TAKT reserialization, AAT Sig_structure), enforces expiry and claim encoding constraints, and uses pure Noir P-256 ECDSA (not stdlib black boxes) with an explicit r != 0 guard. Known-answer tests in Rust and Noir pin digests, serialization, and signatures.

CI splits Noir into separate jobs for ownership-proof and authenticator-assertion. Workspace deps add coset and p256 on world-id-proof; the module is exported as authenticator_attestation (marked WIP in docs).

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[semgrep-code-worldcoin]

Semgrep identified an issue in your code:

The actions/checkout@v6 step uses a mutable version tag that can be silently repointed by attackers, enabling supply-chain attacks where malicious code runs in your CI/CD pipeline.

More details about this

The uses: actions/checkout@v6 step uses a mutable version tag instead of a pinned commit SHA. The v6 tag is a floating reference that the action maintainers can update at any time without warning. If an attacker compromises the actions/checkout repository or GitHub's infrastructure, they could repoint the v6 tag to a malicious version that runs arbitrary code in your workflow.

Here's a realistic attack scenario:

1. Attacker gains access to the actions/checkout repository on GitHub (e.g., through a compromised maintainer account).
2. Attacker updates the v6 tag to point to a new commit containing malicious code that exfiltrates secrets or modifies your build output.
3. Your workflow runs and pulls the tag @v6 without knowing it now resolves to the attacker's malicious commit.
4. The attacker's code executes with full access to your repository secrets, environment variables, and ability to push commits.

Notice that the noir-lang/noirup action in the same file is already pinned to a full commit SHA (7dbe69ccc78877f0200ffa5a40836c953d2cfd8f), so actions/checkout should follow the same pattern.

To resolve this comment:

✨ Commit fix suggestion

1. Replace each mutable GitHub Action tag with a full 40-character commit SHA in the uses: field.
2. Update actions/checkout@v6 to a pinned commit SHA for the actions/checkout release you want to keep. For example, change it to uses: actions/checkout@<40-character-commit-sha> # v6.
3. Apply the same change to every occurrence in this workflow, including both ownership-proof and authenticator-attestation, so no actions/checkout@v6 reference remains.
4. Keep the version comment after the SHA, such as # v6, so it is clear which release the pinned commit corresponds to. Pinning to a commit SHA prevents the action owner from silently moving the referenced version tag to different code.

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[cursor]

Cursor Bugbot has reviewed your changes using default effort and found 1 potential issue.

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