## What changed
- Convert history backend `images` into `input_image` function-call output items alongside encrypted or plaintext history content.
- Keep image data out of logged output and post-tool-use hook responses.
- Reject malformed image attachments instead of silently dropping them.
## Testing
- Cover encrypted and plaintext outputs, supported image detail values, malformed attachments, and propagation into the next model request.
GitOrigin-RevId: a8eee10eb09c637bcfb06a759dd6313caf707e51
