Fix A2AService Compilation and Standardize Zero Trust Mandate Error Handling

[dcplatforms]

This PR addresses critical syntax and consistency issues within the core Zero Trust validation framework of the Open Commerce Protocol (OCP).

Key Changes:

1. Removed duplicate MandateService import in src/services/a2aService.js that caused Jest and ESLint parsing/compilation failures.
2. Aligned MandateService.verifyMandate whitelisting checks to consistently throw standard 'Merchant' instead of 'Recipient' error messages.
3. Handled token expiration errors in MandateService.verifyMandate gracefully, transforming jsonwebtoken's default TokenExpiredError into the correct 'Zero Trust Validation Failed: Mandate has expired' string.
4. Harmonized fallback transaction limit checks in AgentService.performA2ATransfer and updated its unit test suite to properly isolate behavior and verify both local logic and a2aService delegation.

All 45 unit and integration tests are passing perfectly, and linter checks pass with zero errors.

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PR created automatically by Jules for task 7242417214788832787 started by @dcplatforms

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Note

Low Risk
Small consistency and test-isolation changes in validation messaging and imports; no new auth flows or data paths.

Overview
Fixes a duplicate MandateService import in a2aService.js that broke parsing/compilation, and tightens Zero Trust error messaging across mandate verification and agent fallback transfers.

MandateService.verifyMandate now maps JWT TokenExpiredError to a dedicated Mandate has expired message (instead of a generic verification failure), and whitelist failures use Merchant wording to match other mandate paths. AgentService fallback per-transaction limit errors use the same Amount … exceeds agent per-transaction limit phrasing as A2A policy checks.

Unit tests stop wiring a mock a2aService into the default fixture so local limit/counterparty tests hit the fallback path; the delegation case constructs a separate service instance with the mock injected.

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[cursor]

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

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[cursor]

Expired mandate message double-wrapped

Medium Severity

The executeTransfer function unconditionally wraps errors from its initial mandate check, including the Zero Trust Validation Failed: Mandate has expired error from verifyMandate. This results in A2A callers receiving a nested error message for expired mandates, rather than the intended canonical expiry string.

 

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