refactor(settings): 重构设置页面布局和交互

- 优化页面布局，移除侧边栏采用独立页面设计
- 集成 ModelCardSelector 替代下拉选择
- 集成 FontSizePicker 支持字体大小调整
- 顶部导航栏添加主题切换按钮
- 移除冗余的偏好设置和危险区域板块
- 优化整体视觉效果和交互体验

src/app/settings/page.tsx

@@ -2,11 +2,11 @@
 
 import { useState, useEffect } from 'react';
 import Link from 'next/link';
-import { ArrowLeft, Download, Check, Loader2, Eye, EyeOff, RotateCcw } from 'lucide-react';
-import { Sidebar, SidebarToggle } from '@/components/layout/Sidebar';
+import { ArrowLeft, Download, Check, Loader2, Eye, EyeOff, RotateCcw, Moon, Sun, Sparkles, Trash2 } from 'lucide-react';
 import { Toggle } from '@/components/ui/Toggle';
+import { ModelCardSelector } from '@/components/ui/ModelCardSelector';
+import { FontSizePicker } from '@/components/ui/FontSizePicker';
 import { cn } from '@/lib/utils';
-import { currentUser, chatHistories } from '@/data/mock';
 import { useSettings, useModels, useTools } from '@/hooks/useSettings';
 
 // 默认系统提示词
@@ -44,7 +44,6 @@ const DEFAULT_SYSTEM_PROMPT = `你是一个专业、友好的 AI 助手。请遵
 - 承认不确定的地方，不要编造信息`;
 
 export default function SettingsPage() {
-  const [sidebarOpen, setSidebarOpen] = useState(true);
   const { settings, loading, saving, updateSettings } = useSettings();
   const { models, loading: modelsLoading } = useModels();
   const { tools, loading: toolsLoading } = useTools();
@@ -105,6 +104,17 @@ export default function SettingsPage() {
     }
   };
 
+  // 更新字体大小
+  const handleFontSizeChange = async (fontSize: number) => {
+    try {
+      await updateSettings({ fontSize });
+      // 实时应用到页面
+      document.documentElement.style.setProperty('--font-size-base', `${fontSize}px`);
+    } catch (error) {
+      console.error('Failed to update font size:', error);
+    }
+  };
+
   // 切换工具
   const handleToolToggle = async (toolId: string) => {
     const currentTools = settings?.defaultTools || [];
@@ -177,6 +187,17 @@ export default function SettingsPage() {
     setTemperature(value);
   };
 
+  // 切换主题
+  const handleToggleTheme = async () => {
+    const newTheme = settings?.theme === 'dark' ? 'light' : 'dark';
+    try {
+      await updateSettings({ theme: newTheme });
+      document.documentElement.setAttribute('data-theme', newTheme);
+    } catch (error) {
+      console.error('Failed to update theme:', error);
+    }
+  };
+
   if (loading) {
     return (
       <div className="flex min-h-screen items-center justify-center">
@@ -185,55 +206,46 @@ export default function SettingsPage() {
     );
   }
 
+  const isDarkMode = settings?.theme === 'dark';
+
   return (
-    <div className="flex min-h-screen">
-      {/* 侧边栏 */}
-      <Sidebar
-        user={currentUser}
-        chatHistories={chatHistories}
-        isOpen={sidebarOpen}
-        onToggle={() => setSidebarOpen(!sidebarOpen)}
-      />
-
-      {/* 主内容区 */}
-      <main
-        className={cn(
-          'flex-1 min-h-screen transition-all duration-300',
-          sidebarOpen ? 'ml-[var(--sidebar-width)]' : 'ml-0'
-        )}
-      >
-        {/* Header */}
-        <header className="h-[var(--header-height)] px-4 flex items-center">
-          <SidebarToggle onClick={() => setSidebarOpen(!sidebarOpen)} />
-        </header>
-
-        {/* Body */}
-        <div className="px-8 pb-8">
-          <div className="max-w-[800px] mx-auto">
-            {/* 返回链接 */}
+    <div className="min-h-screen bg-[var(--color-bg-secondary)]">
+      {/* 顶部导航栏 */}
+      <header className="sticky top-0 z-10 bg-[var(--color-bg-primary)] border-b border-[var(--color-border-light)]">
+        <div className="max-w-[900px] mx-auto px-6 h-16 flex items-center justify-between">
+          {/* 左侧：返回按钮和标题 */}
+          <div className="flex items-center gap-4">
             <Link
               href="/"
-              className="inline-flex items-center gap-2 text-[var(--color-text-secondary)] text-sm mb-4 hover:text-[var(--color-text-primary)] transition-colors"
+              className="p-2 -ml-2 rounded-lg text-[var(--color-text-secondary)] hover:text-[var(--color-text-primary)] hover:bg-[var(--color-bg-hover)] transition-colors"
+              title="返回聊天"
             >
-              <ArrowLeft size={16} />
-              <span>返回聊天</span>
+              <ArrowLeft size={20} />
             </Link>
-
-            {/* 页面标题 */}
-            <div className="mb-8">
-              <h1 className="text-2xl font-semibold text-[var(--color-text-primary)] mb-2">
-                设置
-              </h1>
-              <p className="text-sm text-[var(--color-text-secondary)]">
-                管理您的账户设置和偏好
-              </p>
+            <div className="flex items-center gap-2">
+              <Sparkles size={24} className="text-[var(--color-primary)]" />
+              <h1 className="text-xl font-semibold text-[var(--color-text-primary)]">Settings</h1>
             </div>
+          </div>
 
-            {/* CCH 配置 */}
-            <SettingsSection
-              title="CCH 服务配置"
-              description="配置 Claude Code Hub 服务连接"
-            >
+          {/* 右侧：主题切换 */}
+          <button
+            onClick={handleToggleTheme}
+            className="p-2 rounded-lg text-[var(--color-text-secondary)] hover:text-[var(--color-text-primary)] hover:bg-[var(--color-bg-hover)] transition-colors"
+            title={isDarkMode ? '切换到浅色模式' : '切换到深色模式'}
+          >
+            {isDarkMode ? <Sun size={20} /> : <Moon size={20} />}
+          </button>
+        </div>
+      </header>
+
+      {/* 主内容区 */}
+      <main className="max-w-[900px] mx-auto px-6 py-8">
+        {/* CCH 配置 */}
+        <SettingsSection
+          title="CCH 服务配置"
+          description="配置 Claude Code Hub 服务连接"
+        >
               <SettingsItem
                 label="CCH 服务地址"
                 description="Claude Code Hub 服务的 URL"
@@ -315,23 +327,36 @@ export default function SettingsPage() {
               title="AI 配置"
               description="配置默认模型和工具"
             >
-              <SettingsItem
-                label="默认模型"
-                description="为新对话选择默认 AI 模型"
-              >
-                <select
-                  className="settings-select"
+              {/* 模型卡片选择 */}
+              <div className="px-5 py-4 border-b border-[var(--color-border-light)]">
+                <div className="text-sm font-medium text-[var(--color-text-primary)] mb-2">
+                  默认模型
+                </div>
+                <div className="text-xs text-[var(--color-text-tertiary)] mb-4">
+                  为新对话选择默认 AI 模型
+                </div>
+                <ModelCardSelector
                   value={settings?.defaultModel || ''}
-                  onChange={(e) => handleModelChange(e.target.value)}
+                  onChange={handleModelChange}
                   disabled={modelsLoading || saving}
-                >
-                  {models.map((model) => (
-                    <option key={model.modelId} value={model.modelId}>
-                      {model.displayName}
-                    </option>
-                  ))}
-                </select>
-              </SettingsItem>
+                  models={models}
+                />
+              </div>
+
+              {/* 字体大小设置 */}
+              <div className="px-5 py-4 border-b border-[var(--color-border-light)]">
+                <div className="text-sm font-medium text-[var(--color-text-primary)] mb-2">
+                  字体大小
+                </div>
+                <div className="text-xs text-[var(--color-text-tertiary)] mb-4">
+                  调整全局字体大小，实时预览效果
+                </div>
+                <FontSizePicker
+                  value={settings?.fontSize || 15}
+                  onChange={handleFontSizeChange}
+                  disabled={saving}
+                />
+              </div>
 
               <SettingsItem
                 label="启用思考模式"
@@ -361,7 +386,7 @@ export default function SettingsPage() {
                         onClick={() => handleToolToggle(tool.toolId)}
                         disabled={saving}
                         className={cn(
-                          'inline-flex items-center gap-2 px-3 py-2 rounded-lg text-sm font-medium transition-all',
+                          'inline-flex items-center gap-2 px-3 py-2 rounded-md text-sm font-medium transition-all',
                           settings?.defaultTools?.includes(tool.toolId)
                             ? 'bg-[var(--color-primary)] text-white'
                             : 'bg-[var(--color-bg-tertiary)] text-[var(--color-text-secondary)] hover:bg-[var(--color-bg-secondary)]'
@@ -465,45 +490,6 @@ export default function SettingsPage() {
               </div>
             </SettingsSection>
 
-            {/* 偏好设置 */}
-            <SettingsSection
-              title="偏好设置"
-              description="自定义您的体验"
-            >
-              <SettingsItem
-                label="主题"
-                description="选择您喜欢的主题"
-              >
-                <select
-                  className="settings-select"
-                  value={settings?.theme || 'light'}
-                  onChange={(e) => handleThemeChange(e.target.value)}
-                  disabled={saving}
-                >
-                  <option value="system">跟随系统</option>
-                  <option value="light">浅色</option>
-                  <option value="dark">深色</option>
-                </select>
-              </SettingsItem>
-
-              <SettingsItem
-                label="语言"
-                description="选择您的首选语言"
-              >
-                <select
-                  className="settings-select"
-                  value={settings?.language || 'zh-CN'}
-                  onChange={(e) => handleLanguageChange(e.target.value)}
-                  disabled={saving}
-                >
-                  <option value="en">English</option>
-                  <option value="zh-CN">简体中文</option>
-                  <option value="zh-TW">繁體中文</option>
-                  <option value="ja">日本語</option>
-                </select>
-              </SettingsItem>
-            </SettingsSection>
-
             {/* 数据与隐私 */}
             <SettingsSection
               title="数据与隐私"
@@ -534,27 +520,12 @@ export default function SettingsPage() {
                 label="清除所有聊天"
                 description="删除所有对话历史"
               >
-                <button className="btn-ghost text-red-600 hover:text-red-700">
+                <button className="btn-ghost text-red-600 hover:text-red-700 inline-flex items-center gap-2">
+                  <Trash2 size={16} />
                   清除
                 </button>
               </SettingsItem>
             </SettingsSection>
-
-            {/* 危险区域 */}
-            <SettingsSection
-              title="危险区域"
-              description="不可逆操作"
-              variant="danger"
-            >
-              <SettingsItem
-                label="删除账户"
-                description="永久删除您的账户和所有数据"
-              >
-                <button className="btn-danger">删除账户</button>
-              </SettingsItem>
-            </SettingsSection>
-          </div>
-        </div>
       </main>
     </div>
   );
@@ -572,7 +543,7 @@ function SettingsSection({ title, description, children, variant = 'default' }:
   return (
     <section
       className={cn(
-        'bg-white border rounded-xl mb-6 overflow-hidden',
+        'bg-white border rounded-md mb-6 overflow-hidden',
         variant === 'danger' ? 'border-red-200' : 'border-[var(--color-border)]'
       )}
     >