[Website] locale-segment routing and shared Lingui factory (#20079)

**1. Shared Lingui factory in `twenty-shared`**

- Extracted `createI18nInstanceFactory` into
`packages/twenty-shared/src/i18n/create-i18n-instance-factory.ts` so
every package gets the same per-render Lingui bootstrap with a
per-locale singleton cache and a `SOURCE_LOCALE` fallback.
- `twenty-emails/src/utils/i18n.utils.ts` now consumes the shared
factory.

**2. `twenty-website-new` Lingui bootstrap + Crowdin wiring**

- `lingui.config.ts`, `src/lib/i18n/*`, `nx run
twenty-website-new:lingui:{extract,compile}`.
- 31 locale PO files generated; minified compiled output kept out of
Prettier and Oxlint.
- `i18n-{push,pull}.yaml` workflows updated to include
`twenty-website-new` in Crowdin sync.

**3. `app/[locale]/...` segment routing with English at the root**

- All marketing routes moved under `src/app/[locale]/`; static
generation preserved (15 routes × 31 locales = 465 prerendered URLs).
- Middleware behavior:
  - `/{en}/...`         → 301 redirect to unprefixed canonical.
  - `/{non-en}/...`     → pass through, set `NEXT_LOCALE` cookie.

### What this PR explicitly does not do (deferred)

- Lingui-wrapping the actual marketing copy. Keys, build pipeline, and
  runtime are wired; copy migration is a separate, reviewer-friendlier
  PR.

Author: mabdullahabaid

.github/workflows/i18n-pull.yaml

@@ -58,6 +58,7 @@ jobs:
           npx nx run twenty-server:lingui:compile --strict
           npx nx run twenty-emails:lingui:compile --strict
           npx nx run twenty-front:lingui:compile --strict
+          npx nx run twenty-website-new:lingui:compile --strict
         continue-on-error: true
 
       - name: Stash any changes before pulling translations
@@ -115,6 +116,7 @@ jobs:
           npx nx run twenty-server:lingui:compile
           npx nx run twenty-emails:lingui:compile
           npx nx run twenty-front:lingui:compile
+          npx nx run twenty-website-new:lingui:compile
           git status
           git add .
           if ! git diff --staged --quiet --exit-code; then

.github/workflows/i18n-push.yaml

@@ -41,6 +41,7 @@ jobs:
           npx nx run twenty-server:lingui:extract
           npx nx run twenty-emails:lingui:extract
           npx nx run twenty-front:lingui:extract
+          npx nx run twenty-website-new:lingui:extract
 
       - name: Check and commit extracted files
         id: check_extract_changes
@@ -60,6 +61,7 @@ jobs:
           npx nx run twenty-server:lingui:compile
           npx nx run twenty-emails:lingui:compile
           npx nx run twenty-front:lingui:compile
+          npx nx run twenty-website-new:lingui:compile
 
       - name: Check and commit compiled files
         id: check_compile_changes

packages/twenty-emails/src/utils/i18n.utils.ts

@@ -1,6 +1,6 @@
-import { setupI18n, type I18n, type Messages } from '@lingui/core';
+import { type Messages } from '@lingui/core';
+import { createI18nInstanceFactory } from 'twenty-shared/i18n';
 import { type APP_LOCALES } from 'twenty-shared/translations';
-import { isDefined } from 'twenty-shared/utils';
 import { messages as afMessages } from '@/locales/generated/af-ZA';
 import { messages as arMessages } from '@/locales/generated/ar-SA';
 import { messages as caMessages } from '@/locales/generated/ca-ES';
@@ -67,20 +67,4 @@ const messages: Record<keyof typeof APP_LOCALES, Messages> = {
   'zh-TW': zhHantMessages,
 };
 
-const i18nInstancesMap: Partial<Record<keyof typeof APP_LOCALES, I18n>> = {};
-
-export const createI18nInstance = (locale: keyof typeof APP_LOCALES): I18n => {
-  if (isDefined(i18nInstancesMap[locale])) {
-    return i18nInstancesMap[locale];
-  }
-
-  const i18nInstance = setupI18n();
-  const localeMessages = messages[locale] ?? messages.en;
-
-  i18nInstance.load(locale, localeMessages);
-  i18nInstance.activate(locale);
-
-  i18nInstancesMap[locale] = i18nInstance;
-
-  return i18nInstance;
-};
+export const createI18nInstance = createI18nInstanceFactory(messages);

packages/twenty-shared/package.json

@@ -66,6 +66,11 @@
       "import": "./dist/database-events.mjs",
       "require": "./dist/database-events.cjs"
     },
+    "./i18n": {
+      "types": "./dist/i18n/index.d.ts",
+      "import": "./dist/i18n.mjs",
+      "require": "./dist/i18n.cjs"
+    },
     "./logic-function": {
       "types": "./dist/logic-function/index.d.ts",
       "import": "./dist/logic-function.mjs",
@@ -118,6 +123,7 @@
     "application",
     "constants",
     "database-events",
+    "i18n",
     "logic-function",
     "metadata",
     "testing",
@@ -142,6 +148,9 @@
       "database-events": [
         "dist/database-events/index.d.ts"
       ],
+      "i18n": [
+        "dist/i18n/index.d.ts"
+      ],
       "logic-function": [
         "dist/logic-function/index.d.ts"
       ],

packages/twenty-shared/project.json

@@ -20,6 +20,8 @@
         "{projectRoot}/constants/dist",
         "{projectRoot}/database-events/package.json",
         "{projectRoot}/database-events/dist",
+        "{projectRoot}/i18n/package.json",
+        "{projectRoot}/i18n/dist",
         "{projectRoot}/logic-function/package.json",
         "{projectRoot}/logic-function/dist",
         "{projectRoot}/metadata/package.json",

packages/twenty-shared/src/i18n/create-i18n-instance-factory.ts

@@ -0,0 +1,29 @@
+import { setupI18n, type I18n, type Messages } from '@lingui/core';
+
+import { type AppLocale } from '@/translations/constants/AppLocales';
+import { SOURCE_LOCALE } from '@/translations/constants/SourceLocale';
+
+export type LocaleMessagesMap = Partial<Record<AppLocale, Messages>>;
+
+export const createI18nInstanceFactory = (
+  messagesByLocale: LocaleMessagesMap,
+) => {
+  const cache: Partial<Record<AppLocale, I18n>> = {};
+
+  return (locale: AppLocale): I18n => {
+    const cached = cache[locale];
+    if (cached !== undefined) {
+      return cached;
+    }
+
+    const fallbackMessages = messagesByLocale[SOURCE_LOCALE] ?? {};
+    const localeMessages = messagesByLocale[locale] ?? fallbackMessages;
+
+    const i18n = setupI18n();
+    i18n.load(locale, localeMessages);
+    i18n.activate(locale);
+
+    cache[locale] = i18n;
+    return i18n;
+  };
+};

packages/twenty-shared/src/i18n/index.ts

@@ -0,0 +1,11 @@
+/*
+ * _____                    _
+ *|_   _|_      _____ _ __ | |_ _   _
+ *  | | \ \ /\ / / _ \ '_ \| __| | | | Auto-generated file
+ *  | |  \ V  V /  __/ | | | |_| |_| | Any edits to this will be overridden
+ *  |_|   \_/\_/ \___|_| |_|\__|\__, |
+ *                              |___/
+ */
+
+export type { LocaleMessagesMap } from './create-i18n-instance-factory';
+export { createI18nInstanceFactory } from './create-i18n-instance-factory';

packages/twenty-website-new/.oxlintrc.json

@@ -4,7 +4,7 @@
   "categories": {
     "correctness": "error"
   },
-  "ignorePatterns": ["node_modules"],
+  "ignorePatterns": ["node_modules", "src/locales/generated"],
   "rules": {
     "func-style": ["error", "declaration", { "allowArrowFunctions": true }],
     "no-console": "off",

packages/twenty-website-new/.prettierignore

@@ -0,0 +1 @@
+src/locales/generated

packages/twenty-website-new/lingui.config.ts

@@ -0,0 +1,22 @@
+import { defineConfig } from '@lingui/conf';
+import { formatter } from '@lingui/format-po';
+import { APP_LOCALES, SOURCE_LOCALE } from 'twenty-shared/translations';
+
+export default defineConfig({
+  sourceLocale: SOURCE_LOCALE,
+  locales: Object.values(APP_LOCALES),
+  pseudoLocale: 'pseudo-en',
+  fallbackLocales: {
+    'pseudo-en': 'en',
+    default: SOURCE_LOCALE,
+  },
+  catalogs: [
+    {
+      path: '<rootDir>/src/locales/{locale}',
+      include: ['src'],
+    },
+  ],
+  catalogsMergePath: '<rootDir>/src/locales/generated/{locale}',
+  compileNamespace: 'ts',
+  format: formatter({ lineNumbers: false, printLinguiId: true }),
+});