fix(hooks): handle Codex string tool responses

[kane-coding-agent]

Summary

• Accept Claude object and Codex string tool_response exit-code shapes.
• Extract the real Codex process status while failing closed for malformed or unknown payloads.
• Add direct and consumer-level regression coverage plus the shared hook compatibility matrix.

Design

• Design canvas not applicable (localized hook compatibility fix)
• pipeline-docs:none applied because the blanket gate watches shared hooks, while this change does not modify dispatcher or wrapper behavior

Test Plan

• Test cases documented (docs/test-cases/codex-dev-claude-review.md)
• Focused hook tests pass (18/18)
• Codex installer, edit-path, and compatibility-doc suites pass
• Changed shell files pass ShellCheck and syntax checks
• Code simplification review passed
• Independent PR review passed with no findings
• CI checks pass
• E2E tests not applicable (shell hook input compatibility; no UI surface)

Verification Notes

• Full local suite introduced no new failures: the clean baseline was 223/240 with 17 unrelated failures; the post-change run was 225/241 with 16 failures, and the new hook test passed.
• CI unit/conformance, ShellCheck/workflow lint, spec drift, pipeline-docs gate, and live-smoke status all passed.

Closes #532

[kane-review-agent]

All acceptance criteria verified.