Fix empty emails critical bug (#13465)

Fixes https://github.com/twentyhq/twenty/issues/13398

This bug was introduced by https://github.com/twentyhq/twenty/pull/13215

The emails were empty in scenarios where the user wasn't authenticated
(reset passwords for instance) because in `hydrateGraphqlRequest` the
information about the locale was added only if the user was
authenticated `!this.isTokenPresent(request)`. So the locale was
undefined making ` i18n.activate(undefined) ` fail silently resulting in
an empty email.

packages/twenty-server/src/engine/metadata-modules/object-metadata/utils/__tests__/resolve-object-metadata-standard-override.util.spec.ts

@@ -478,4 +478,53 @@ describe('resolveObjectMetadataStandardOverride', () => {
       expect(mockI18n._).toHaveBeenCalledWith('auto.translation.id');
     });
   });
+
+  describe('Undefined locale handling', () => {
+    it('should use SOURCE_LOCALE fallback when locale is undefined for standard object', () => {
+      const objectMetadata = {
+        labelSingular: 'Standard Label',
+        labelPlural: 'Standard Labels',
+        description: 'Standard Description',
+        icon: 'default-icon',
+        isCustom: false,
+        standardOverrides: {
+          labelSingular: 'Source Override',
+        },
+      };
+
+      const result = resolveObjectMetadataStandardOverride(
+        objectMetadata,
+        'labelSingular',
+        undefined,
+      );
+
+      expect(result).toBe('Source Override');
+      expect(mockGenerateMessageId).not.toHaveBeenCalled();
+      expect(mockI18n._).not.toHaveBeenCalled();
+    });
+
+    it('should fall back to auto translation when locale is undefined and no SOURCE_LOCALE override exists', () => {
+      mockI18n._.mockReturnValue('Auto Translated Label');
+      mockGenerateMessageId.mockReturnValue('auto.translation.id');
+
+      const objectMetadata = {
+        labelSingular: 'Standard Label',
+        labelPlural: 'Standard Labels',
+        description: 'Standard Description',
+        icon: 'default-icon',
+        isCustom: false,
+        standardOverrides: undefined,
+      };
+
+      const result = resolveObjectMetadataStandardOverride(
+        objectMetadata,
+        'labelSingular',
+        undefined,
+      );
+
+      expect(result).toBe('Auto Translated Label');
+      expect(mockGenerateMessageId).toHaveBeenCalledWith('Standard Label');
+      expect(mockI18n._).toHaveBeenCalledWith('auto.translation.id');
+    });
+  });
 });

packages/twenty-server/src/engine/metadata-modules/object-metadata/utils/resolve-object-metadata-standard-override.util.ts

@@ -19,6 +19,8 @@ export const resolveObjectMetadataStandardOverride = (
   labelKey: 'labelPlural' | 'labelSingular' | 'description' | 'icon',
   locale: keyof typeof APP_LOCALES | undefined,
 ): string => {
+  const safeLocale = locale ?? SOURCE_LOCALE;
+
   if (objectMetadata.isCustom) {
     return objectMetadata[labelKey] ?? '';
   }
@@ -32,11 +34,10 @@ export const resolveObjectMetadataStandardOverride = (
 
   if (
     isDefined(objectMetadata.standardOverrides?.translations) &&
-    isDefined(locale) &&
     labelKey !== 'icon'
   ) {
     const translationValue =
-      objectMetadata.standardOverrides.translations[locale]?.[labelKey];
+      objectMetadata.standardOverrides.translations[safeLocale]?.[labelKey];
 
     if (isDefined(translationValue)) {
       return translationValue;
@@ -44,7 +45,7 @@ export const resolveObjectMetadataStandardOverride = (
   }
 
   if (
-    locale === SOURCE_LOCALE &&
+    safeLocale === SOURCE_LOCALE &&
     isNonEmptyString(objectMetadata.standardOverrides?.[labelKey])
   ) {
     return objectMetadata.standardOverrides[labelKey] ?? '';

packages/twenty-server/src/engine/middlewares/middleware.service.ts

@@ -128,6 +128,10 @@ export class MiddlewareService {
 
   public async hydrateGraphqlRequest(request: Request) {
     if (!this.isTokenPresent(request)) {
+      request.locale =
+        (request.headers['x-locale'] as keyof typeof APP_LOCALES) ??
+        SOURCE_LOCALE;
+
       return;
     }