[WebUI] Enter submits on IME composition confirm, preventing Japanese input

[MogamiTsuchikawa]

Description

When using OpenCode WebUI with Input Method Editors (IME) such as Japanese, Chinese, or Korean, pressing Enter to confirm input composition causes the message to be sent immediately, even though the composition is still in progress. This is a critical issue for users who depend on IME languages, as they cannot use the natural way to confirm character composition.

Plugins

None

OpenCode version

1.1.2

Steps to reproduce

1. Open OpenCode WebUI
2. Switch to an IME language (e.g., Japanese, Chinese, Korean)
3. Start typing a message using the IME (e.g., type a Japanese sentence)
4. Press Enter to confirm the composed text 5. The message is sent immediately instead of inserting the confirmed text

Screenshot and/or share link

No response

Operating System

macOS

Terminal

None

[github-actions]

This issue might be a duplicate of existing issues. Please check:

• Korean characters disappear in the input prompt when using WezTerm/Ghostty #2013: Korean characters disappear in the input prompt when using WezTerm/Ghostty (IME composition issues on macOS)
• Korean (Hangul) characters display as broken/garbled in input field #3493: Korean (Hangul) characters display as broken/garbled in input field (CJK rendering issues)
• Keybinds #4997: Keybinds (pinned keybinds issue covering keyboard input handling)

These issues also involve IME/keyboard input handling. Feel free to ignore if your specific case involves the WebUI rather than the TUI.

[MogamiTsuchikawa]

I fixed with this PR.
#6952