Improve Korean (Hangul) input in the terminal — composing text is not visible

Request

Korean (Hangul) input in the interactive prompt is hard to use: the IME composing (pre-edit) text is not shown in the input box, so you cannot see what you are typing until each syllable/word is committed. The same terminal works fine with Codex and Claude Code.

Please improve Hangul input handling in the terminal TUI so composing text is visible while typing.

Environment

• Command Code 1.56.0 (latest)
• macOS arm64 (Darwin 25.6.0)
• iTerm2 3.6.11, TERM=xterm-256color, LANG=ko_KR.UTF-8, Korean 2-set IME

Steps to reproduce

1. Run cmd in iTerm2 with the Korean IME active
2. Focus the prompt input and type 한글
3. No pre-edit is displayed while composing - only the committed text appears

Notes

• dist/cli.mjs has no composition handling at all (isComposing, compositionupdate, preedit, markedText: zero occurrences), and the kitty keyboard protocol is pushed at startup (resolveKittyKeyboard with disambiguateEscapeCodes). There is no setting, config key, or env var to opt out.
• ctrl+g (external editor) is the only usable workaround right now.

首先，使用韩语 2-set IME 在交互式提示符中复现该问题，然后检查 dist/cli.mjs 以及 resolveKittyKeyboard 和 disambiguateEscapeCodes 附近的启动路径。跟踪终端输入如何到达 TUI，并确定组合事件的处理位置。当输入时能够显示 Hangul 预编辑文本，且已提交的文本仍能正常工作时，即表示完成。