feat(i18n): add Brazilian Portuguese (pt-BR) locale (#171)

## Summary
- Adds full Brazilian Portuguese translation (820/820 UI strings) as a
third supported locale next to `en` and `zh-CN`.
- Auto-detects `pt-*` system locales; users can also switch manually
from the topbar toggle or Settings → Appearance → Language.
- Default locale (`DEFAULT_LOCALE`) stays `en`; no behavior change for
existing users.

## What's inside
- `packages/i18n/src/locales/pt-BR.json` — 820 UI strings, full parity
with `en.json`
- `packages/templates/src/locales/pt-BR.ts` — 4 built-in demos (title,
description, prompt)
- `packages/templates/src/examples/locales/pt-BR.ts` — 21 hub examples
(title, description)
- `packages/i18n/src/index.ts` — register `pt-BR` in `availableLocales`,
`resources`, `normalizeLocale` (accepts `pt`, `pt-BR`, `pt_br`, `pt-*`)
- Templates registries pointed to the new pt-BR files (no `en` fallback)
- `Settings.tsx` dropdown + `LanguageToggle.tsx` cycle now include
`pt-BR`
- `langPtBR` label added to `en.json` and `zh-CN.json` so the dropdown
works across all locales

## Translation quality notes
- Terminology glossary applied consistently (tweaks → Ajustes, design
system → design system, snapshot → snapshot, etc.)
- `{{interpolations}}` and `_one`/`_other` plural suffixes preserved
- 32 strings kept identical to EN (product names, file paths, unit
suffixes, tech jargon) — no mistranslations
- Reviewed end-to-end for tone, grammar, and accuracy (standardized
`novamente`, fixed `redacted → redigido` bug, `Nota fiscal → Fatura` for
semantic accuracy, etc.)

## Test plan
- [ ] \`pnpm lint && pnpm typecheck && pnpm test\` all pass locally
(pre-push hook confirms)
- [ ] App boots with zero \`missing translation\` / \`unsupported
locale\` warnings
- [ ] Settings → Appearance → Language shows \`Português (BR)\`;
selection persists across restart
- [ ] Topbar globe toggle cycles \`EN → ZH → PT → EN\`
- [ ] System locale \`pt-BR\` auto-selects pt-BR on first launch
- [ ] Hub Examples gallery and built-in demos render in PT
- [ ] No UI clipping from longer PT strings (sidebar, settings,
onboarding)

---------

Signed-off-by: Sun-sunshine06 <Sun-sunshine06@users.noreply.github.com>
Signed-off-by: David Fernandes <davidggffernandes@gmail.com>

Author: DavidgFernandes

apps/desktop/src/renderer/src/components/LanguageToggle.tsx

@@ -6,12 +6,17 @@ import { useEffect, useState } from 'react';
 
 const noDragStyle = { WebkitAppRegion: 'no-drag' } as CSSProperties;
 
+const LOCALE_CYCLE: Locale[] = ['en', 'zh-CN', 'pt-BR'];
+
 function nextLocale(locale: Locale): Locale {
-  return locale === 'en' ? 'zh-CN' : 'en';
+  const i = LOCALE_CYCLE.indexOf(locale);
+  return LOCALE_CYCLE[(i + 1) % LOCALE_CYCLE.length] ?? 'en';
 }
 
 function localeLabel(locale: Locale): string {
-  return locale === 'zh-CN' ? 'ZH' : 'EN';
+  if (locale === 'zh-CN') return 'ZH';
+  if (locale === 'pt-BR') return 'PT';
+  return 'EN';
 }
 
 export function LanguageToggle() {

apps/desktop/src/renderer/src/components/Settings.tsx

@@ -1719,6 +1719,7 @@ function AppearanceTab() {
             options={[
               { value: 'en', label: t('settings.appearance.langEn') },
               { value: 'zh-CN', label: t('settings.appearance.langZhCN') },
+              { value: 'pt-BR', label: t('settings.appearance.langPtBR') },
             ]}
           />
         </Row>

packages/i18n/src/index.ts

@@ -16,16 +16,18 @@ import i18next from 'i18next';
 import { useCallback } from 'react';
 import { initReactI18next, useTranslation } from 'react-i18next';
 import en from './locales/en.json';
+import ptBR from './locales/pt-BR.json';
 import zhCN from './locales/zh-CN.json';
 
-export const availableLocales = ['en', 'zh-CN'] as const;
+export const availableLocales = ['en', 'zh-CN', 'pt-BR'] as const;
 export type Locale = (typeof availableLocales)[number];
 
 const DEFAULT_LOCALE: Locale = 'en';
 
 const resources = {
   en: { translation: en },
   'zh-CN': { translation: zhCN },
+  'pt-BR': { translation: ptBR },
 } as const;
 
 export function isSupportedLocale(value: string | undefined | null): value is Locale {
@@ -40,6 +42,9 @@ export function normalizeLocale(value: string | undefined | null): Locale {
   if (lower === 'zh' || lower.startsWith('zh-hans') || lower === 'zh-cn' || lower === 'zh_cn') {
     return 'zh-CN';
   }
+  if (lower === 'pt-br' || lower === 'pt_br' || lower === 'pt' || lower.startsWith('pt-')) {
+    return 'pt-BR';
+  }
   if (lower.startsWith('en')) return 'en';
   console.warn(
     `[i18n] unsupported locale "${value}", falling back to "${DEFAULT_LOCALE}". ` +

packages/i18n/src/locales/en.json

@@ -333,7 +333,8 @@
       "languageHint": "Language changes take effect immediately.",
       "languageLoadFailed": "Failed to load language",
       "langEn": "English",
-      "langZhCN": "中文 (简体)"
+      "langZhCN": "中文 (简体)",
+      "langPtBR": "Português (BR)"
     },
     "language": {
       "label": "Language",