feat: dynamic title

frontend/src/core/i18n/locales/en-US.ts

@@ -100,6 +100,14 @@ export const enUS: Translations = {
     searchChats: "Search chats",
   },
 
+  // Page titles (document title)
+  pages: {
+    appName: "DeerFlow",
+    chats: "Chats",
+    newChat: "New chat",
+    untitled: "Untitled",
+  },
+
   // Tool calls
   toolCalls: {
     moreSteps: (count: number) => `${count} more step${count === 1 ? "" : "s"}`,

frontend/src/core/i18n/locales/types.ts

@@ -94,6 +94,14 @@ export interface Translations {
     searchChats: string;
   };
 
+  // Page titles (document title)
+  pages: {
+    appName: string;
+    chats: string;
+    newChat: string;
+    untitled: string;
+  };
+
   // Tool calls
   toolCalls: {
     moreSteps: (count: number) => string;

frontend/src/core/i18n/locales/zh-CN.ts

@@ -98,6 +98,14 @@ export const zhCN: Translations = {
     searchChats: "搜索对话",
   },
 
+  // Page titles (document title)
+  pages: {
+    appName: "DeerFlow",
+    chats: "对话",
+    newChat: "新对话",
+    untitled: "未命名",
+  },
+
   // Tool calls
   toolCalls: {
     moreSteps: (count: number) => `查看其他 ${count} 个步骤`,