Feature Request: Add Traditional Chinese (zh-TW) UI localization

Feature Request

Add Traditional Chinese (繁體中文, zh-TW) localization for the Claude Code UI.

Description

Currently, all UI strings in Claude Code are hardcoded in English — including status messages (e.g., companion muted), error messages (e.g., Error editing file), spinner text, command outputs (/context, /cost, etc.), and dialog prompts.

While the language setting controls Claude's response language, there is no way to localize the application interface itself.

Requested Scope

• System/status messages (e.g., "companion muted", "Error editing file")
• Spinner verbs and tips
• Permission prompts and confirmation dialogs
• Command output labels (/cost, /context, /compact, etc.)
• Plan mode UI text

Why zh-TW specifically

• Traditional Chinese is used in Taiwan, Hong Kong, and Macau
• It differs significantly from Simplified Chinese (zh-CN) in both characters and terminology
• Issue #40819 requests zh-CN support, but zh-TW has distinct localization needs

Related Issues

• #31413 — UI language localization support (general)
• #40819 — Simplified Chinese (zh-CN) support