Bug Report: Chinese IME text cannot be typed in Codex Desktop chat input

Summary
Codex Desktop chat input accepts direct English typing, but Chinese IME composition text cannot be entered. Pasting Chinese text works.

Environment
App: Codex Desktop
App version: 26.601.21317
Bundle version: 3511
Bundle identifier: com.openai.codex
macOS version: 26.3.1, build 25D2128
Platform: Darwin 25.3.0 arm64
Input method: Apple Simplified Chinese Pinyin (com.apple.inputmethod.SCIM.ITABC)
Steps To Reproduce
Open Codex Desktop on macOS.
Click the chat input box.
Switch input source to Apple Simplified Chinese Pinyin.
Type Chinese text using pinyin.
Observe that Chinese composition/candidate text does not enter the chat input.
Switch to English input and type letters.
Observe that English text can be entered normally.
Copy Chinese text from another app and paste it into the Codex chat input.
Observe that pasted Chinese text appears normally.
Expected Behavior
Chinese IME composition should work in the Codex Desktop chat input, including candidate selection and committing text into the input box.

Actual Behavior
English typing works, and pasted Chinese text works, but Chinese IME composition text cannot be typed directly into the chat input.

Impact
This makes normal Chinese conversation with Codex Desktop inconvenient because users have to type Chinese in another app and paste it back into Codex.

Notes
The behavior suggests that the input box receives normal key events but does not correctly handle macOS IME composition/commit events for Chinese input.