Queue MCP tool images for model input

[david-strejc]

Summary

• convert MCP tool image blocks into data URIs and queue them as upcoming InputItem::Image
• keep accompanying text blocks from the tool result so they are replayed to the model alongside the image
• warn if queuing fails, ensuring we still answer the tool call

Testing

• cargo test -p codex-core
• cargo test --all-features

[github-actions]

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[david-strejc]

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

[david-strejc]

Rechecked after signing the CLA.

[david-strejc]

recheck

[david-strejc]

recheck

[etraut-openai]

Thanks for the contribution, and apologies for the slow response. We've received many PRs, and we don't have the bandwidth on the codex team to review all of them.

It appears that this PR is no longer needed. Support for MCP tool images was recently added, so this should work in the latest version of codex. Let us know if you run into any problems with it.