- Added 'x-ae-ignore-extra-fields' header to support stripping unknown fields in POST/PATCH.
- Added automatic resolution of '*_id_random' strings to integer IDs in 'sanitize_payload'.
- Refactored 'post_obj' to return structured (field -> message) validation errors in 'meta.details'.
- Updated 'mk_resp' to support non-string 'details' in response metadata.
- Added 'tests/verify_feedback_fixes.py' to validate logic changes.
Ref: V3 API Refinement Feedback from mcp_agent.
