refactor(background): 简化背景功能为静态图片

动态背景切换功能因效果不佳暂时移除。本次重构将背景实现简化为仅支持单张静态图片

src/main.tsx

@@ -5,7 +5,7 @@ import "./index.css";
 import "@radix-ui/themes/styles.css";
 import { Theme } from "@radix-ui/themes";
 import { Header } from "@/components/sections/Header";
-import DynamicPseudoBackground from "@/components/sections/Background";
+import Background from "@/components/sections/Background";
 import { useTheme } from "@/hooks/useTheme";
 import { NodeDataProvider } from "@/contexts/NodeDataContext";
 import { LiveDataProvider } from "@/contexts/LiveDataContext";
@@ -46,10 +46,8 @@ const App = () => {
       appearance="inherit"
       scaling="110%"
       style={{ backgroundColor: "transparent" }}>
-      {/* 使用动态背景组件 */}
-      {publicSettings && (
-        <DynamicPseudoBackground publicSettings={publicSettings} />
-      )}
+      {/* 使用背景组件 */}
+      {publicSettings && <Background publicSettings={publicSettings} />}
       <div className="min-h-screen flex flex-col text-sm">
         <Header
           viewMode={viewMode}