style(界面): 优化聊天页面和侧边栏样式

- 聊天页面集成 ChatHeader 组件显示助手信息
- 添加淡入、滑入等动画效果样式
- 优化侧边栏布局和新对话按钮交互
- 统一分类标签的视觉样式

src/app/chat/[id]/page.tsx

@@ -6,6 +6,7 @@ import { Share2, MoreHorizontal, Loader2, Square, Clock, ChevronDown, Pencil, Tr
 import { Sidebar, SidebarToggle } from '@/components/layout/Sidebar';
 import { ChatInput } from '@/components/features/ChatInput';
 import { MessageBubble } from '@/components/features/MessageBubble';
+import { ChatHeaderInfo } from '@/components/features/ChatHeader';
 import { cn } from '@/lib/utils';
 import { useConversation, useConversations } from '@/hooks/useConversations';
 import { useStreamChat, type ChatMessage } from '@/hooks/useStreamChat';
@@ -263,6 +264,19 @@ export default function ChatPage({ params }: PageProps) {
     setEnableThinking(!enableThinking);
   };
 
+  // 切换模型（持久化到数据库）
+  const handleModelChange = async (modelId: string) => {
+    if (!conversation || modelId === selectedModelId) return;
+
+    try {
+      await updateConversation(chatId, { model: modelId });
+      setSelectedModelId(modelId);
+    } catch (error) {
+      console.error('Failed to change model:', error);
+      throw error;
+    }
+  };
+
   // 转换模型格式
   const modelOptions = models.map((m) => ({
     id: m.modelId,
@@ -305,89 +319,91 @@ export default function ChatPage({ params }: PageProps) {
         )}
       >
         {/* 固定顶部 Header */}
-        <header className="h-[var(--header-height)] px-4 flex items-center justify-between border-b border-[var(--color-border)] bg-[var(--color-bg-primary)] sticky top-0 z-10">
-          <div className="flex items-center gap-3">
-            <SidebarToggle onClick={() => setSidebarOpen(!sidebarOpen)} />
+        <header className="px-4 py-2 flex flex-col gap-1 border-b border-[var(--color-border)] bg-[var(--color-bg-primary)] sticky top-0 z-10">
+          {/* 第一行：标题和操作按钮 */}
+          <div className="flex items-center justify-between">
+            <div className="flex items-center gap-3">
+              <SidebarToggle onClick={() => setSidebarOpen(!sidebarOpen)} />
 
-            {/* 标题区域 - 可点击显示下拉菜单 */}
-            {isEditingTitle ? (
-              // 编辑模式
-              <div className="flex items-center gap-2">
-                <input
-                  ref={titleInputRef}
-                  type="text"
-                  value={editingTitle}
-                  onChange={(e) => setEditingTitle(e.target.value)}
-                  onKeyDown={handleTitleKeyDown}
-                  onBlur={handleCancelRename}
-                  className="px-2 py-1 text-base font-medium bg-[var(--color-bg-secondary)] border border-[var(--color-border)] rounded text-[var(--color-text-primary)] focus:outline-none focus:border-[var(--color-primary)] max-w-[300px]"
-                  disabled={isSavingTitle}
-                />
-                <button
-                  onMouseDown={(e) => {
-                    e.preventDefault();
-                    handleSubmitRename();
-                  }}
-                  disabled={isSavingTitle || !editingTitle.trim()}
-                  className="p-1 text-green-500 hover:bg-[var(--color-bg-hover)] rounded disabled:opacity-50"
-                  title="Confirm"
-                >
-                  {isSavingTitle ? (
-                    <Loader2 size={16} className="animate-spin" />
-                  ) : (
-                    <Check size={16} />
+              {/* 标题区域 - 可点击显示下拉菜单 */}
+              {isEditingTitle ? (
+                // 编辑模式
+                <div className="flex items-center gap-2">
+                  <input
+                    ref={titleInputRef}
+                    type="text"
+                    value={editingTitle}
+                    onChange={(e) => setEditingTitle(e.target.value)}
+                    onKeyDown={handleTitleKeyDown}
+                    onBlur={handleCancelRename}
+                    className="px-2 py-1 text-base font-medium bg-[var(--color-bg-secondary)] border border-[var(--color-border)] rounded text-[var(--color-text-primary)] focus:outline-none focus:border-[var(--color-primary)] max-w-[300px]"
+                    disabled={isSavingTitle}
+                  />
+                  <button
+                    onMouseDown={(e) => {
+                      e.preventDefault();
+                      handleSubmitRename();
+                    }}
+                    disabled={isSavingTitle || !editingTitle.trim()}
+                    className="p-1 text-green-500 hover:bg-[var(--color-bg-hover)] rounded disabled:opacity-50"
+                    title="Confirm"
+                  >
+                    {isSavingTitle ? (
+                      <Loader2 size={16} className="animate-spin" />
+                    ) : (
+                      <Check size={16} />
+                    )}
+                  </button>
+                  <button
+                    onMouseDown={(e) => {
+                      e.preventDefault();
+                      handleCancelRename();
+                    }}
+                    disabled={isSavingTitle}
+                    className="p-1 text-[var(--color-text-tertiary)] hover:bg-[var(--color-bg-hover)] rounded disabled:opacity-50"
+                    title="Cancel"
+                  >
+                    <X size={16} />
+                  </button>
+                </div>
+              ) : (
+                // 正常模式 - 显示标题和下拉菜单
+                <div className="relative" ref={titleMenuRef}>
+                  <button
+                    onClick={() => setTitleMenuOpen(!titleMenuOpen)}
+                    className="flex items-center gap-1 text-base font-medium text-[var(--color-text-primary)] hover:bg-[var(--color-bg-hover)] px-2 py-1 rounded-lg transition-colors max-w-[300px]"
+                  >
+                    <span className="truncate">{conversation?.title || 'New Chat'}</span>
+                    <ChevronDown size={16} className={cn(
+                      'flex-shrink-0 transition-transform',
+                      titleMenuOpen && 'rotate-180'
+                    )} />
+                  </button>
+
+                  {/* 下拉菜单 */}
+                  {titleMenuOpen && (
+                    <div className="absolute left-0 top-full mt-1 bg-[var(--color-bg-primary)] border border-[var(--color-border)] rounded-lg shadow-lg py-1 z-20 min-w-[140px]">
+                      <button
+                        onClick={handleStartRename}
+                        className="w-full px-3 py-2 text-left text-sm text-[var(--color-text-secondary)] hover:bg-[var(--color-bg-hover)] flex items-center gap-2"
+                      >
+                        <Pencil size={14} />
+                        Rename
+                      </button>
+                      <button
+                        onClick={handleDeleteConversation}
+                        className="w-full px-3 py-2 text-left text-sm text-red-500 hover:bg-[var(--color-bg-hover)] flex items-center gap-2"
+                      >
+                        <Trash2 size={14} />
+                        Delete
+                      </button>
+                    </div>
                   )}
-                </button>
-                <button
-                  onMouseDown={(e) => {
-                    e.preventDefault();
-                    handleCancelRename();
-                  }}
-                  disabled={isSavingTitle}
-                  className="p-1 text-[var(--color-text-tertiary)] hover:bg-[var(--color-bg-hover)] rounded disabled:opacity-50"
-                  title="Cancel"
-                >
-                  <X size={16} />
-                </button>
-              </div>
-            ) : (
-              // 正常模式 - 显示标题和下拉菜单
-              <div className="relative" ref={titleMenuRef}>
-                <button
-                  onClick={() => setTitleMenuOpen(!titleMenuOpen)}
-                  className="flex items-center gap-1 text-base font-medium text-[var(--color-text-primary)] hover:bg-[var(--color-bg-hover)] px-2 py-1 rounded-lg transition-colors max-w-[300px]"
-                >
-                  <span className="truncate">{conversation?.title || 'New Chat'}</span>
-                  <ChevronDown size={16} className={cn(
-                    'flex-shrink-0 transition-transform',
-                    titleMenuOpen && 'rotate-180'
-                  )} />
-                </button>
-
-                {/* 下拉菜单 */}
-                {titleMenuOpen && (
-                  <div className="absolute left-0 top-full mt-1 bg-[var(--color-bg-primary)] border border-[var(--color-border)] rounded-lg shadow-lg py-1 z-20 min-w-[140px]">
-                    <button
-                      onClick={handleStartRename}
-                      className="w-full px-3 py-2 text-left text-sm text-[var(--color-text-secondary)] hover:bg-[var(--color-bg-hover)] flex items-center gap-2"
-                    >
-                      <Pencil size={14} />
-                      Rename
-                    </button>
-                    <button
-                      onClick={handleDeleteConversation}
-                      className="w-full px-3 py-2 text-left text-sm text-red-500 hover:bg-[var(--color-bg-hover)] flex items-center gap-2"
-                    >
-                      <Trash2 size={14} />
-                      Delete
-                    </button>
-                  </div>
-                )}
-              </div>
-            )}
-          </div>
-          <div className="flex items-center gap-2">
-            {/* 思考模式开关 */}
+                </div>
+              )}
+            </div>
+            <div className="flex items-center gap-2">
+              {/* 思考模式开关 */}
             <button
               onClick={handleThinkingToggle}
               className={cn(
@@ -415,6 +431,17 @@ export default function ChatPage({ params }: PageProps) {
             >
               <MoreHorizontal size={18} />
             </button>
+            </div>
+          </div>
+
+          {/* 第二行：助手和模型信息 */}
+          <div className="pl-12">
+            <ChatHeaderInfo
+              assistant={conversation?.assistant || null}
+              currentModel={selectedModelId}
+              models={modelOptions}
+              onModelChange={handleModelChange}
+            />
           </div>
         </header>
 

src/app/globals.css

@@ -258,6 +258,26 @@ body {
   animation: scaleInFast 0.15s ease-out;
 }
 
+.animate-scale-in {
+  animation: scaleInFast 0.2s ease-out;
+}
+
+/* 卡片淡入上浮动画 */
+@keyframes fadeInUp {
+  from {
+    opacity: 0;
+    transform: translateY(8px);
+  }
+  to {
+    opacity: 1;
+    transform: translateY(0);
+  }
+}
+
+.animate-fade-in-up {
+  animation: fadeInUp 0.3s ease-out both;
+}
+
 /* ========================================
    响应式设计
    ======================================== */

src/components/layout/Sidebar.tsx

@@ -2,11 +2,11 @@
 
 import Link from 'next/link';
 import { usePathname, useRouter } from 'next/navigation';
-import { Plus, PanelLeft, Trash2, MoreHorizontal, Loader2, Pencil, Check, X } from 'lucide-react';
+import { Plus, PanelLeft, Trash2, MoreHorizontal, Loader2, Pencil, Check, X, Bot } from 'lucide-react';
 import { UserMenu } from '@/components/ui/UserMenu';
+import { NewChatModal } from '@/components/features/NewChatModal';
 import { cn } from '@/lib/utils';
 import { useConversations } from '@/hooks/useConversations';
-import { useSettings } from '@/hooks/useSettings';
 import { useAuth } from '@/providers/AuthProvider';
 import type { Conversation } from '@/drizzle/schema';
 import { useState, useRef, useEffect } from 'react';
@@ -19,14 +19,13 @@ interface SidebarProps {
 export function Sidebar({ isOpen = true }: SidebarProps) {
   const pathname = usePathname();
   const router = useRouter();
-  const { conversations, loading, createConversation, deleteConversation, updateConversation } = useConversations();
-  const { settings } = useSettings();
+  const { conversations, loading, deleteConversation, updateConversation } = useConversations();
   const { user } = useAuth();
-  const [creatingChat, setCreatingChat] = useState(false);
   const [menuOpen, setMenuOpen] = useState<string | null>(null);
   const [editingId, setEditingId] = useState<string | null>(null);
   const [editingTitle, setEditingTitle] = useState('');
   const [isSubmitting, setIsSubmitting] = useState(false);
+  const [showNewChatModal, setShowNewChatModal] = useState(false);
   const inputRef = useRef<HTMLInputElement>(null);
   const menuRef = useRef<HTMLDivElement>(null);
 
@@ -53,23 +52,9 @@ export function Sidebar({ isOpen = true }: SidebarProps) {
     };
   }, [menuOpen]);
 
-  // 创建新对话
-  const handleNewChat = async () => {
-    if (creatingChat) return;
-
-    try {
-      setCreatingChat(true);
-      const newConversation = await createConversation({
-        model: settings?.defaultModel || 'claude-sonnet-4-20250514',
-        tools: settings?.defaultTools || [],
-        enableThinking: settings?.enableThinking || false,
-      });
-      router.push(`/chat/${newConversation.conversationId}`);
-    } catch (error) {
-      console.error('Failed to create conversation:', error);
-    } finally {
-      setCreatingChat(false);
-    }
+  // 创建新对话 - 显示选择助手弹框
+  const handleNewChat = () => {
+    setShowNewChatModal(true);
   };
 
   // 删除对话
@@ -150,18 +135,29 @@ export function Sidebar({ isOpen = true }: SidebarProps) {
         <div className="px-4 py-2">
           <button
             onClick={handleNewChat}
-            disabled={creatingChat}
-            className="flex items-center gap-2 text-[var(--color-primary)] text-sm font-medium py-2 hover:opacity-80 transition-opacity disabled:opacity-50"
+            className="flex items-center gap-2 text-[var(--color-primary)] text-sm font-medium py-2 hover:opacity-80 transition-opacity"
           >
-            {creatingChat ? (
-              <Loader2 size={18} className="animate-spin" />
-            ) : (
-              <Plus size={18} />
-            )}
+            <Plus size={18} />
             <span>New chat</span>
           </button>
         </div>
 
+        {/* 助手库入口 */}
+        <div className="px-4 pb-2">
+          <Link
+            href="/assistants"
+            className={cn(
+              'flex items-center gap-2 text-sm font-medium py-2 transition-colors',
+              pathname === '/assistants'
+                ? 'text-[var(--color-primary)]'
+                : 'text-[var(--color-text-secondary)] hover:text-[var(--color-primary)]'
+            )}
+          >
+            <Bot size={18} />
+            <span>助手库</span>
+          </Link>
+        </div>
+
         {/* 聊天列表 */}
         <nav className="flex-1 overflow-y-auto px-2 flex flex-col gap-1">
           {loading ? (
@@ -301,6 +297,12 @@ export function Sidebar({ isOpen = true }: SidebarProps) {
           onClick={() => setMenuOpen(null)}
         />
       )}
+
+      {/* 新建对话弹框 */}
+      <NewChatModal
+        isOpen={showNewChatModal}
+        onClose={() => setShowNewChatModal(false)}
+      />
     </>
   );
 }