feat: Implement scroll position management with a new setting, add a back-to-top button, and extend search cache duration.

components/settings/DisplaySettings.tsx

@@ -11,20 +11,41 @@ import { Switch } from '@/components/ui/Switch';
 interface DisplaySettingsProps {
     realtimeLatency: boolean;
     searchDisplayMode: SearchDisplayMode;
+    rememberScrollPosition: boolean;
     onRealtimeLatencyChange: (enabled: boolean) => void;
     onSearchDisplayModeChange: (mode: SearchDisplayMode) => void;
+    onRememberScrollPositionChange: (enabled: boolean) => void;
 }
 
 export function DisplaySettings({
     realtimeLatency,
     searchDisplayMode,
+    rememberScrollPosition,
     onRealtimeLatencyChange,
     onSearchDisplayModeChange,
+    onRememberScrollPositionChange,
 }: DisplaySettingsProps) {
     return (
         <div className="bg-[var(--glass-bg)] border border-[var(--glass-border)] rounded-[var(--radius-2xl)] shadow-[var(--shadow-sm)] p-6 mb-6">
             <h2 className="text-xl font-semibold text-[var(--text-color)] mb-4">显示设置</h2>
 
+            {/* Remember Scroll Position Toggle */}
+            <div className="mb-6">
+                <div className="flex items-center justify-between">
+                    <div>
+                        <h3 className="font-medium text-[var(--text-color)]">记住滚动位置</h3>
+                        <p className="text-sm text-[var(--text-color-secondary)] mt-1">
+                            退出或刷新页面后，自动恢复到之前的滚动位置
+                        </p>
+                    </div>
+                    <Switch
+                        checked={rememberScrollPosition}
+                        onChange={onRememberScrollPositionChange}
+                        ariaLabel="记住滚动位置开关"
+                    />
+                </div>
+            </div>
+
             {/* Real-time Latency Toggle */}
             <div className="mb-6">
                 <div className="flex items-center justify-between">