add translation

apps/app/public/static/locales/en_US/translation.json

@@ -590,7 +590,9 @@
       "ai_assistant_deleted_success": "Assistant deleted",
       "ai_assistant_deleted_failed": "Failed to delete assistant",
       "thread_deleted_success": "Thread deleted",
-      "thread_deleted_failed": "Failed to delete thread"
+      "thread_deleted_failed": "Failed to delete thread",
+      "ai_assistant_set_default_success": "Default assistant set successfully",
+      "ai_assistant_set_default_failed": "Failed to set default assistant"
     }
   },
   "link_edit": {

apps/app/public/static/locales/fr_FR/translation.json

@@ -585,7 +585,9 @@
       "ai_assistant_deleted_success": "Assistant supprimé",
       "ai_assistant_deleted_failed": "Échec de la suppression de l'assistant",
       "thread_deleted_success": "Discussion supprimée",
-      "thread_deleted_failed": "Échec de la suppression de la discussion"
+      "thread_deleted_failed": "Échec de la suppression de la discussion",
+      "ai_assistant_set_default_success": "Assistant par défaut défini avec succès",
+      "ai_assistant_set_default_failed": "Échec de la définition de l'assistant par défaut"
     }
   },
   "link_edit": {

apps/app/public/static/locales/ja_JP/translation.json

@@ -623,7 +623,9 @@
       "ai_assistant_deleted_success": "アシスタントを削除しました",
       "ai_assistant_deleted_failed": "アシスタントの削除に失敗しました",
       "thread_deleted_success": "スレッドを削除しました",
-      "thread_deleted_failed": "スレッドの削除に失敗しました"
+      "thread_deleted_failed": "スレッドの削除に失敗しました",
+      "ai_assistant_set_default_success": "デフォルトアシスタントを設定しました",
+      "ai_assistant_set_default_failed": "デフォルトアシスタントの設定に失敗しました"
     }
   },
   "link_edit": {

apps/app/public/static/locales/zh_CN/translation.json

@@ -580,7 +580,9 @@
       "ai_assistant_deleted_success": "已删除助手",
       "ai_assistant_deleted_failed": "删除助手失败",
       "thread_deleted_success": "已删除会话",
-      "thread_deleted_failed": "删除会话失败"
+      "thread_deleted_failed": "删除会话失败",
+      "ai_assistant_set_default_success": "已成功设置默认助手",
+      "ai_assistant_set_default_failed": "设置默认助手失败"
     }
   },
   "link_edit": {