feat(i18n): add Traditional Chinese (zh-TW) localization for frontend and CLI (#6320)

* feat(i18n): add Traditional Chinese (zh-TW) localization for frontend and CLI

- Add src/i18n/messages/zh-TW.json translating frontend web UI
- Add bin/cli/locales/zh-TW.json translating CLI commands and descriptors
- Register zh-TW in config/i18n.json and docs/guides/I18N.md
- Update scripts/i18n/generate-multilang.mjs matching the new locale setup

* fix: update i18n locale count from 42 to 43 after adding zh-TW

The docs strict checker (check-docs-counts-sync.mjs) validates that
README.md and I18N.md reflect the real locale count. Adding zh-TW
bumped the count from 42 → 43.

* fix(i18n): translate providers free-filter labels in zh-TW (#6694 guard)

Co-authored-by: diegosouzapw <8016841+diegosouzapw@users.noreply.github.com>

---------

Co-authored-by: Diego Rodrigues de Sa e Souza <diegosouza.pw@gmail.com>
Co-authored-by: Diego Rodrigues de Sa e Souza <8016841+diegosouzapw@users.noreply.github.com>
Co-authored-by: lunkerchen <lunkerchen@users.noreply.github.com>

config/i18n.json

@@ -340,6 +340,14 @@
       "native": "中文 (简体)",
       "english": "Chinese (Simplified)",
       "flag": "🇨🇳"
+    },
+    {
+      "code": "zh-TW",
+      "label": "ZH-TW",
+      "name": "中文 (繁體)",
+      "native": "中文 (繁體)",
+      "english": "Chinese (Traditional)",
+      "flag": "🇹🇼"
     }
   ]
 }

docs/README.md

@@ -177,7 +177,7 @@ Mermaid sources and exported SVG/PNG diagrams referenced from the docs above. Se
 
 ## i18n/
 
-Translated mirrors of the documentation in 42 locales. See [i18n/README.md](i18n/README.md) for the supported language list.
+Translated mirrors of the documentation in 43 locales. See [i18n/README.md](i18n/README.md) for the supported language list.
 
 ## screenshots/
 

docs/guides/I18N.md

@@ -6,7 +6,7 @@ lastUpdated: 2026-06-28
 
 # i18n — Internationalization Guide
 
-OmniRoute supports **42 languages** with full dashboard UI translation, translated documentation, and RTL support for Arabic and Hebrew.
+OmniRoute supports **43 languages** with full dashboard UI translation, translated documentation, and RTL support for Arabic and Hebrew.
 
 🌐 **Languages:** 🇺🇸 [English](./I18N.md) | 🇧🇷 [Português (Brasil)](../i18n/pt-BR/docs/guides/I18N.md) | 🇪🇸 [Español](../i18n/es/docs/guides/I18N.md) | 🇫🇷 [Français](../i18n/fr/docs/guides/I18N.md) | 🇩🇪 [Deutsch](../i18n/de/docs/guides/I18N.md) | 🇮🇹 [Italiano](../i18n/it/docs/guides/I18N.md) | 🇷🇺 [Русский](../i18n/ru/docs/guides/I18N.md) | 🇨🇳 [中文 (简体)](../i18n/zh-CN/docs/guides/I18N.md) | 🇯🇵 [日本語](../i18n/ja/docs/guides/I18N.md) | 🇰🇷 [한국어](../i18n/ko/docs/guides/I18N.md) | 🇸🇦 [العربية](../i18n/ar/docs/guides/I18N.md) | 🇮🇳 [हिन्दी](../i18n/hi/docs/guides/I18N.md) | 🇹🇭 [ไทย](../i18n/th/docs/guides/I18N.md) | 🇹🇷 [Türkçe](../i18n/tr/docs/guides/I18N.md) | 🇺🇦 [Українська](../i18n/uk-UA/docs/guides/I18N.md) | 🇻🇳 [Tiếng Việt](../i18n/vi/docs/guides/I18N.md) | 🇧🇬 [Български](../i18n/bg/docs/guides/I18N.md) | 🇩🇰 [Dansk](../i18n/da/docs/guides/I18N.md) | 🇫🇮 [Suomi](../i18n/fi/docs/guides/I18N.md) | 🇮🇱 [עברית](../i18n/he/docs/guides/I18N.md) | 🇭🇺 [Magyar](../i18n/hu/docs/guides/I18N.md) | 🇮🇩 [Bahasa Indonesia](../i18n/id/docs/guides/I18N.md) | 🇲🇾 [Bahasa Melayu](../i18n/ms/docs/guides/I18N.md) | 🇳🇱 [Nederlands](../i18n/nl/docs/guides/I18N.md) | 🇳🇴 [Norsk](../i18n/no/docs/guides/I18N.md) | 🇵🇹 [Português (Portugal)](../i18n/pt/docs/guides/I18N.md) | 🇷🇴 [Română](../i18n/ro/docs/guides/I18N.md) | 🇵🇱 [Polski](../i18n/pl/docs/guides/I18N.md) | 🇸🇰 [Slovenčina](../i18n/sk/docs/guides/I18N.md) | 🇸🇪 [Svenska](../i18n/sv/docs/guides/I18N.md) | 🇵🇭 [Filipino](../i18n/phi/docs/guides/I18N.md) | 🇨🇿 [Čeština](../i18n/cs/docs/guides/I18N.md)
 
@@ -134,6 +134,7 @@ README variants) are not yet handled by the new pipeline and are still used.
 | `uk-UA` | Українська           | No  | `uk`                  |
 | `vi`    | Tiếng Việt           | No  | `vi`                  |
 | `zh-CN` | 中文 (简体)          | No  | `zh-CN`               |
+| `zh-TW` | 中文 (繁體)          | No  | `zh-TW`               |
 
 ## Adding a New Language
 
@@ -241,7 +242,7 @@ python3 scripts/i18n/i18n_autotranslate.py \
 - Scans `docs/i18n/` markdown files for English paragraphs
 - Skips code blocks, tables, and already-translated content
 - Sends paragraphs to LLM with technical translation system prompt
-- Supports all 42 languages
+- Supports all 43 languages
 
 ## CLI i18n
 
@@ -250,7 +251,7 @@ The `omniroute` CLI has its own i18n layer separate from the Next.js dashboard.
 ### How it works
 
 - Every user-facing string in CLI commands goes through `t("module.key", vars)` from `bin/cli/i18n.mjs`.
-- Catalogs are JSON files in `bin/cli/locales/` — 42 ship out-of-the-box.
+- Catalogs are JSON files in `bin/cli/locales/` — 43 ship out-of-the-box.
 - Locale falls back to `en` for any missing key, so partial translations are valid.
 - The source of truth for available locales is `config/i18n.json` (shared with the dashboard).
 
@@ -301,7 +302,7 @@ invocation. Use `config lang set` to persist.
 
 ### Available locales
 
-42 locale files ship in `bin/cli/locales/`. Full translations: `en`, `pt-BR`.
+43 locale files ship in `bin/cli/locales/`. Full translations: `en`, `pt-BR`.
 Scaffold-only (all keys fall back to `en`): `bn`, `gu`, `he`, `in`, `mr`, `ms`, `phi`, `sw`, `ta`, `te`, `ur`.
 All other 29 locales have `common` + `program` keys translated.
 
@@ -348,12 +349,13 @@ python3 scripts/i18n/validate_translation.py -l cs
 - **Placeholder mismatches** — ICU placeholders that don't match between source and translation
 
 **Exit codes:**
-| Code | Meaning |
-|------|---------|
-| 0 | OK |
-| 1 | Generic error |
-| 2 | Missing strings (hard error) |
-| 3 | Untranslated warning (soft) |
+
+| Code | Meaning                      |
+| ---- | ---------------------------- |
+| 0    | OK                           |
+| 1    | Generic error                |
+| 2    | Missing strings (hard error) |
+| 3    | Untranslated warning (soft)  |
 
 **Environment:** Set `TRANSLATION_LANG=cs` or use `-l cs` flag.
 

scripts/i18n/generate-multilang.mjs

@@ -97,6 +97,15 @@ const LOCALE_SPECS = [
     readmeName: "中文 (简体)",
     docsName: "中文 (简体)",
   },
+  {
+    code: "zh-TW",
+    googleTl: "zh-TW",
+    label: "ZH-TW",
+    flag: "🇹🇼",
+    languageName: "中文 (繁體)",
+    readmeName: "中文 (繁體)",
+    docsName: "中文 (繁體)",
+  },
   {
     code: "de",
     googleTl: "de",
@@ -414,7 +423,7 @@ const LOCALE_SPECS = [
   },
 ];
 
-const EXISTING_README_CODES = new Set(["pt-BR", "es", "fr", "it", "ru", "zh-CN", "de"]);
+const EXISTING_README_CODES = new Set(["pt-BR", "es", "fr", "it", "ru", "zh-CN", "zh-TW", "de"]);
 const RTL_LOCALES = new Set(["ar", "fa", "he", "ur"]);
 
 const URL_MAX_TEXT_LENGTH = 1800;