fix: handle Codex OAuth responses missing output

[bamsby]

Summary

• Coerce completed OpenAI Responses objects with missing/null output to an empty output list before SDK parsing raises a TypeError
• Keep incomplete, failed, and already-populated responses untouched
• Treat the observed SDK TypeError as a Codex stream completion failure so Hermes can use the existing retry/fallback path
• Add regression coverage for the parser compatibility helper and streaming fallback

Security / secrets check

• Scanned added lines and committed diff for hardcoded secret assignments and common API key/token patterns
• No API keys, OAuth tokens, or secrets were found in the diff
• The change does not log or transmit credentials; it only normalizes response object shape and uses existing fallback behavior

Test Plan

• env -u PYTHONHOME -u PYTHONPATH PYTHONPATH="/c/Users/g_nan/AppData/Local/hermes/hermes-agent" ./venv/Scripts/python -m py_compile agent/codex_runtime.py tests/run_agent/test_run_agent_codex_responses.py
• env -u PYTHONHOME -u PYTHONPATH PYTHONPATH="/c/Users/g_nan/AppData/Local/hermes/hermes-agent" ./venv/Scripts/python -m pytest -o addopts= tests/run_agent/test_run_agent_codex_responses.py -q -p no:timeout

[alt-glitch]

Duplicate of #32884 — same Codex Responses null output recovery. Root cause tracked in #11179.

[teknium1]

Closing as duplicate — the Codex null-output fix has been merged via #32963 (cherry-picked from @carltonawong's PR #32890). Thanks for the help during the outage. Closes #11179.