feat(ee): Add article translation via LLM in help center (#14136)

Adds the ability to translate help center articles to other languages using Captain's LLM infrastructure. Translated articles are created as drafts linked to the source article.

Fixes
https://linear.app/chatwoot/issue/CW-6901/translate-article-to-another-language

**How to test**

1. Navigate to Help Center → Articles for a portal with multiple locales
2. Click the three-dot menu on any article → "Translate"
3. Select a target language and category → click Translate
4. Switch to the target locale — the translated article appears as a
draft
5. Try translating the same article again — a warning shows the existing
translation with a link to open it in a new tab
6. Click "Overwrite and translate" to replace the existing translation


https://github.com/user-attachments/assets/1d2e991b-f0ac-403a-bcc1-2181b5731ea4

app/javascript/dashboard/store/modules/helpCenterArticles/actions.js

@@ -166,4 +166,18 @@ export const actions = {
       throw error;
     }
   },
+
+  bulkTranslate: async (
+    _,
+    { portalSlug, articleIds, locale, categoryId, force = false }
+  ) => {
+    const { data } = await articlesAPI.bulkTranslate({
+      portalSlug,
+      articleIds,
+      locale,
+      categoryId,
+      force,
+    });
+    return data;
+  },
 };