Add agent job runner for CSV batches

[daveaitel-openai]

Summary

• make spawn_agents_on_csv synchronous with mandatory auto-export
• drop status/wait/export tools from the public surface; keep worker report tool internal-use only
• emit agent-job progress updates and render a compact progress bar + ETA while suppressing agent-job subagent output in exec

Testing

• just fix -p codex-core
• just fix -p codex-exec
• just fmt
• cargo test -p codex-core
• cargo test -p codex-exec

[github-actions]

Thank you for your submission, we really appreciate it. Like many open-source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution. You can sign the CLA by just posting a Pull Request Comment same as the below format.

---

I have read the CLA Document and I hereby sign the CLA

---

_{You can retrigger this bot by commenting recheck in this Pull Request. Posted by the CLA Assistant Lite bot.}