In the Chinese input state, the option key does not work correctly

### Checklist

- [x] Using latest version on the [App Store](http://itunes.apple.com/app/id1156707581)
- [x] Read the [docs](http://blink.sh/docs/)
- [x] Searched for [existing GitHub issues](https://github.com/blinksh/blink/issues)

### Configuration

14.0.5 (409)
iPad OS 15.2
configuration

### Describe the bug

I use the Neovim editor. In the Chinese input state, the option key does not work correctly.
However, under the English input state, it can work normally.

In the configuration I set 'As modifier'. Then, my neovim can use the meta key combination mapping, but Chinese input state, and without making it work, I still enter the digraph:

I tested it on the computer, and even if Chinese input state, it still works.

I need you to help me solve this problem.

In the Chinese input state, the option key does not work correctly.

No source files, tests, or entry points are named. Reproduce the issue on iPadOS 15.2 with Blink 14.0.5 (409), Neovim, the Chinese input state, and the Option key configured as a modifier; done means Option-based meta mappings work in Chinese input as they do in English.

Written by the indexing model from the issue text.