OpenAI Agents SDK adapter

[cesarebernardis]

Introducing the Agent Spec adapter for the OpenAI Agents SDK

[nasseur]

Internal regression failed: Build ID #164

[nasseur]

Internal regression failed: Build ID #165

[seratch]

Thanks for building this! I left a few minor suggestions and I hope they're helpful.

[oracle-contributor-agreement]

Thank you for your pull request and welcome to our community! To contribute, please sign the Oracle Contributor Agreement (OCA).
The following contributors of this PR have not signed the OCA:

• seratch@openai.com

To sign the OCA, please create an Oracle account and sign the OCA in Oracle's Contributor Agreement Application.

When signing the OCA, please provide your GitHub username. After signing the OCA and getting an OCA approval from Oracle, this PR will be automatically updated.

If you are an Oracle employee, please make sure that you are a member of the main Oracle GitHub organization, and your membership in this organization is public.

[nasseur]

Internal regression failed: Build ID #167

[nasseur]

Internal regression succeeded 🍏: Build ID #168

[cesarebernardis]

This PR requires openai and, consequently, langchain to be upgraded, which is currently being done in #58