Use WP Codebox v0.12.11 release

[chubes4]

Summary

• Advance all Docs Agent WP Codebox workflow and validation references to v0.12.11.
• Validate allowlisted uploads and normalized lifecycle failures from WP Codebox run 29306539573.

How to test

1. Clone WP Codebox at tag v0.12.11 and set WP_CODEBOX_DIR to that checkout.
2. Run php tests/validate-docs-agent-bundle.php.
3. Run php tests/validate-external-native-package-sources.php.
4. Run WP_CODEBOX_DIR=/path/to/wp-codebox php tests/validate-wp-codebox-run-agent-task-contract.php.
5. Run php tests/repair-docs-links-smoke.php, AGENTS_API_DIR=/path/to/agents-api php tests/native-agent-import.php, and actionlint .github/workflows/*.yml.

AI assistance

• AI assistance: Yes
• Tool(s): openai/gpt-5.6-terra via OpenCode
• Used for: Updated release references, contract fixtures, documentation, and validation coverage; Chris remains responsible for review and merge.