parse expected failure abort code

[batatovich]

Summary

Adds the logic to parse abort codes for expected_failure attributes in test mode.

Changes Made

• Parser now process abort codes and clever errors for expected_failure attributes
• Modified test engine to manage abort codes and assert them when expected_failure(abort_code = ...) is used.

Checklist

• I have read the contributing guidelines.
• I have added/updated tests where appropriate.
• I have run relevant tests locally.
• I have updated relevant documentation (if applicable).
• I have disclosed any AI assistance per AI_POLICY.md.