feat: Add bulk actions for help center articles (translate, status change, delete) (#14137)

Fixes
https://linear.app/chatwoot/issue/CW-6950/support-bulk-actions-for-publish-archive-move-to-draft-delete-in

How to test

1. Go to Help Center → Articles
2. Select articles using checkboxes → bulk bar appears
3. Click Publish/Draft/Archive → articles update, list refreshes
4. Click Delete → confirmation dialog → articles removed
5. Click Translate (requires Captain enabled) → select locale + category
→ translation starts
6. Try translating to a locale that already has translations → warning
with links to existing articles → "Overwrite and translate" proceeds
8. Single article: click three-dot menu → Translate → same dialog opens
for that article



https://github.com/user-attachments/assets/7c76495e-f89e-4456-92bd-a6639a9992f4

---------

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

app/javascript/dashboard/i18n/locale/en/helpCenter.json

@@ -590,6 +590,10 @@
         "CATEGORY_PLACEHOLDER": "Select a category",
         "OPTIONAL": "(optional)",
         "CONFIRM": "Translate",
+        "SELECT_ALL": "Select all ({count})",
+        "SELECTED_COUNT": "{count} selected",
+        "CLEAR_SELECTION": "Clear selection",
+        "TRANSLATE_BUTTON": "Translate",
         "CONFIRM_OVERWRITE": "Overwrite and translate",
         "DUPLICATE_WARNING": "A translation already exists for this article in the selected language. | Translations already exist for {count} articles in the selected language.",
         "DUPLICATE_CONFIRM_HINT": "Click translate again to overwrite the existing translation.",
@@ -597,6 +601,20 @@
           "SUCCESS_MESSAGE": "Translation in progress. The article will appear as a draft once ready.",
           "ERROR_MESSAGE": "Failed to start translation. Please try again."
         }
+      },
+      "BULK_ACTIONS": {
+        "PUBLISH": "Publish",
+        "DRAFT": "Draft",
+        "ARCHIVE": "Archive",
+        "TRANSLATE": "Translate",
+        "DELETE": "Delete",
+        "STATUS_SUCCESS": "Articles updated successfully",
+        "STATUS_ERROR": "Failed to update articles",
+        "DELETE_CONFIRM_TITLE": "Delete article | Delete {count} articles",
+        "DELETE_CONFIRM_DESCRIPTION": "This will permanently delete the selected article. This action cannot be undone. | This will permanently delete {count} selected articles. This action cannot be undone.",
+        "DELETE_CONFIRM": "Delete",
+        "DELETE_SUCCESS": "Articles deleted successfully",
+        "DELETE_ERROR": "Failed to delete articles"
       }
     },
     "CATEGORY_PAGE": {