feat(i18n): add Traditional Chinese localization (#3093)

* Add Traditional Chinese localization

* fix: address zh-TW formatting and token units

- Format `zh-TW.json` with Prettier.
- Use Traditional Chinese `萬` and `億` units for zh-TW token summaries.
- Add usage formatting coverage for Traditional Chinese locale aliases.

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Co-authored-by: Jason <farion1231@gmail.com>

src/types.ts

@@ -342,7 +342,7 @@ export interface Settings {
   // User has confirmed the common config first-run notice
   commonConfigConfirmed?: boolean;
   // 首选语言（可选，默认中文）
-  language?: "en" | "zh" | "ja";
+  language?: "en" | "zh" | "zh-TW" | "ja";
 
   // 主页面显示的应用（默认全部显示）
   visibleApps?: VisibleApps;