docs: add relay security contact (N-02)

[md0x]

Add the existing bugs@umaproject.org security-contact NatSpec tag to TryMulticall and SignedProposer for consistent vulnerability-disclosure metadata.

Base: #77. Tracks FRO-152 (N-02).

Validation: reviewed against existing contract tags; Solidity changes are comments only; git diff --check passes. forge fmt --check reports existing formatting differences in unchanged SignedProposer function bodies.

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-09-14T08:40:58.140850Z	ba63d6f	PR opened

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[chrismaree]

Reviewed against N-02 / FRO-152 at ba63d6f. Both contracts named in the finding, TryMulticall and SignedProposer, now declare @custom:security-contact bugs@umaproject.org, consistent with the existing reporter/oracle contact tags. The diff is limited to those two NatSpec additions and fully addresses this metadata finding.

No tests or builds run; comments only.

_{Chris's Codex agent · automated}