Feature Request: Add Chinese (zh-CN) system UI language support

Feature Request

Is your feature request related to a problem?

Currently, the language setting in Claude Code only affects Claude's response language. All system-level UI text — such as tool use permission prompts, rejection messages, confirmation dialogs, and other framework-generated messages — remains in English. This creates a mixed-language experience for Chinese-speaking users.

Describe the solution you'd like

Add full Chinese (zh-CN) localization support for Claude Code's system UI, including:

• Tool use permission confirmation prompts
• Tool rejection / denial messages
• System status messages and notifications
• Error messages generated by the framework
• Any other framework-level text that is currently hardcoded in English

Ideally, this should be controlled by the existing language setting in settings.json, so when a user sets "language": "zh-CN", both Claude's responses and the system UI are displayed in Chinese.

Describe alternatives you've considered

• A plugin/skill system for community-contributed translations
• An i18n configuration file that users can customize

Additional context

There is a growing number of Chinese-speaking developers using Claude Code. Native language support for the system UI would significantly improve the user experience.

Thank you!