Add translation for 'no_recent_chat' message in ThreadList component

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

@@ -498,6 +498,7 @@
   "sidebar_ai_assistant": {
     "reference_pages_label": "Reference pages",
     "recent_chat": "Recent chat",
+    "no_recent_chat": "No recent chat",
     "placeholder": "Ask me anything.",
     "knowledge_assistant_placeholder": "Ask me anything.",
     "editor_assistant_placeholder": "Can I help you with anything?",

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

@@ -493,6 +493,7 @@
   "sidebar_ai_assistant": {
     "reference_pages_label": "Pages de référence",
     "recent_chat": "Chat récent",
+    "no_recent_chat": "Pas de chat récent",
     "knowledge_assistant_placeholder": "Demandez-moi n'importe quoi.",
     "editor_assistant_placeholder": "Puis-je vous aider ?",
     "summary_mode_label": "Mode résumé",

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

@@ -531,6 +531,7 @@
   "sidebar_ai_assistant": {
     "reference_pages_label": "参照するページ",
     "recent_chat": "最近のチャット",
+    "no_recent_chat": "チャットがありません",
     "knowledge_assistant_placeholder": "ききたいことを入力してください",
     "editor_assistant_placeholder": "お手伝いできることはありますか？",
     "summary_mode_label": "要約モード",

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

@@ -488,6 +488,7 @@
   "sidebar_ai_assistant": {
     "reference_pages_label": "参考页面",
     "recent_chat": "最近聊天",
+    "No recent chat": "最近没有聊天",
     "knowledge_assistant_placeholder": "问我任何问题。",
     "editor_assistant_placeholder": "有什么需要帮忙的吗？",
     "summary_mode_label": "摘要模式",

apps/app/src/features/openai/client/components/AiAssistant/AiAssistantSidebar/ThreadList.tsx

@@ -1,5 +1,7 @@
 import React, { useCallback } from 'react';
 
+import { useTranslation } from 'react-i18next';
+
 import type { IThreadRelationHasId } from '~/features/openai/interfaces/thread-relation';
 
 import { useAiAssistantSidebar } from '../../../stores/ai-assistant';
@@ -11,6 +13,7 @@ const moduleClass = styles['thread-list'] ?? '';
 
 
 export const ThreadList: React.FC = () => {
+  const { t } = useTranslation();
   const { openChat, data: aiAssistantSidebarData } = useAiAssistantSidebar();
   const { data: threads } = useSWRxThreads(aiAssistantSidebarData?.aiAssistantData?._id);
 
@@ -23,10 +26,18 @@ export const ThreadList: React.FC = () => {
     openChat(aiAssistantData, threadData);
   }, [aiAssistantSidebarData?.aiAssistantData, openChat]);
 
+  if (threads == null || threads.length === 0) {
+    return (
+      <p className="text-body-secondary">
+        {t('sidebar_ai_assistant.no_recent_chat')}
+      </p>
+    );
+  }
+
   return (
     <>
       <ul className={`list-group ${moduleClass}`}>
-        {threads?.map(thread => (
+        {threads.map(thread => (
           <li
             onClick={() => { openChatHandler(thread) }}
             key={thread._id}