feat(website): 官网多页面 + 中英文切换 + Kimi 风格科技风重设计

- 多页路由：首页 / 功能 / 更新日志 / 下载（HashRouter，适配 GitHub Pages）
- 中英文切换（zh/en 双语文案 + localStorage 记忆）
- Kimi 品牌配色（中性灰 + 蓝）+ 科技风（网格底纹 / 辉光按钮 / 渐变强调词）
- 更新日志页：运行时同步 GitHub Releases，localStorage 缓存 1h，网络失败回退内置列表
- 功能页 8 张截图卡片；下载页含自动更新说明
- 修复资源路径 404（asset() + %BASE_URL%）；自托管 Inter/Fira Code 字体

website/src/App.tsx

@@ -0,0 +1,52 @@
+import { useEffect } from "react";
+import { Route, Routes, useLocation } from "react-router-dom";
+import Nav from "./components/Nav";
+import Hero from "./sections/Hero";
+import Features from "./sections/Features";
+import Changelog from "./sections/Changelog";
+import Download from "./sections/Download";
+import Privacy from "./sections/Privacy";
+import CTA from "./sections/CTA";
+import Footer from "./components/Footer";
+
+function ScrollToTop() {
+  const { pathname } = useLocation();
+  useEffect(() => {
+    window.scrollTo(0, 0);
+  }, [pathname]);
+  return null;
+}
+
+const homePage = (
+  <>
+    <Hero />
+    <CTA />
+  </>
+);
+
+export default function App() {
+  return (
+    <div className="flex min-h-screen flex-col">
+      <Nav />
+      <main className="flex-1">
+        <ScrollToTop />
+        <Routes>
+          <Route path="/" element={homePage} />
+          <Route
+            path="/features"
+            element={
+              <>
+                <Features />
+                <Privacy />
+              </>
+            }
+          />
+          <Route path="/changelog" element={<Changelog />} />
+          <Route path="/download" element={<Download />} />
+          <Route path="*" element={homePage} />
+        </Routes>
+      </main>
+      <Footer />
+    </div>
+  );
+}