文档: 新增 Docusaurus 官网与双语文档，README 切换为英文默认 (#39)

- 新建 docs-site/ Docusaurus 项目，支持 en + zh-Hans 双语
- 从 README 迁移内容为独立文档页面：
  - Getting Started（安装、快速开始）
  - Deployment（Docker、裸机、Nginx、配置参考）
  - Features（备份类型、存储后端、SAP HANA、多节点集群、通知）
  - Reference（API、CLI）
  - Development（开发、贡献）
- 自定义 BackupX 主题色、logo、落地页组件
- 新增 .github/workflows/docs.yml，Actions 自动构建并发布到 GitHub Pages
- README.md 切换为英文，中文版挪到 README.zh-CN.md，两者均精简为导航型
- 配置站点 URL：https://awuqing.github.io/BackupX/

docs-site/docusaurus.config.ts

@@ -0,0 +1,129 @@
+import {themes as prismThemes} from 'prism-react-renderer';
+import type {Config} from '@docusaurus/types';
+import type * as Preset from '@docusaurus/preset-classic';
+
+// BackupX 官方站点 — 托管在 GitHub Pages
+// https://awuqing.github.io/BackupX/
+const config: Config = {
+  title: 'BackupX',
+  tagline: 'Self-hosted server backup management — one binary, one command',
+  favicon: 'img/favicon.ico',
+
+  future: {
+    v4: true,
+  },
+
+  url: 'https://awuqing.github.io',
+  baseUrl: '/BackupX/',
+
+  organizationName: 'Awuqing',
+  projectName: 'BackupX',
+  deploymentBranch: 'gh-pages',
+  trailingSlash: false,
+
+  onBrokenLinks: 'warn',
+  markdown: {
+    hooks: {
+      onBrokenMarkdownLinks: 'warn',
+    },
+  },
+
+  i18n: {
+    defaultLocale: 'en',
+    locales: ['en', 'zh-Hans'],
+    localeConfigs: {
+      en: {label: 'English', direction: 'ltr', htmlLang: 'en-US'},
+      'zh-Hans': {label: '简体中文', direction: 'ltr', htmlLang: 'zh-CN'},
+    },
+  },
+
+  presets: [
+    [
+      'classic',
+      {
+        docs: {
+          sidebarPath: './sidebars.ts',
+          editUrl: 'https://github.com/Awuqing/BackupX/edit/main/docs-site/',
+        },
+        blog: false,
+        theme: {
+          customCss: './src/css/custom.css',
+        },
+      } satisfies Preset.Options,
+    ],
+  ],
+
+  themeConfig: {
+    image: 'img/social-card.png',
+    colorMode: {
+      respectPrefersColorScheme: true,
+    },
+    navbar: {
+      title: 'BackupX',
+      logo: {
+        alt: 'BackupX Logo',
+        src: 'img/logo.svg',
+      },
+      items: [
+        {
+          type: 'docSidebar',
+          sidebarId: 'docs',
+          position: 'left',
+          label: 'Docs',
+        },
+        {
+          href: 'https://github.com/Awuqing/BackupX/releases',
+          label: 'Downloads',
+          position: 'left',
+        },
+        {
+          type: 'localeDropdown',
+          position: 'right',
+        },
+        {
+          href: 'https://github.com/Awuqing/BackupX',
+          label: 'GitHub',
+          position: 'right',
+        },
+      ],
+    },
+    footer: {
+      style: 'dark',
+      links: [
+        {
+          title: 'Docs',
+          items: [
+            {label: 'Introduction', to: '/docs/intro'},
+            {label: 'Quick Start', to: '/docs/getting-started/quick-start'},
+            {label: 'Installation', to: '/docs/getting-started/installation'},
+          ],
+        },
+        {
+          title: 'Features',
+          items: [
+            {label: 'SAP HANA', to: '/docs/features/sap-hana'},
+            {label: 'Multi-Node Cluster', to: '/docs/features/multi-node'},
+            {label: 'API Reference', to: '/docs/reference/api'},
+          ],
+        },
+        {
+          title: 'More',
+          items: [
+            {label: 'GitHub', href: 'https://github.com/Awuqing/BackupX'},
+            {label: 'Releases', href: 'https://github.com/Awuqing/BackupX/releases'},
+            {label: 'Docker Hub', href: 'https://hub.docker.com/r/awuqing/backupx'},
+            {label: 'Issues', href: 'https://github.com/Awuqing/BackupX/issues'},
+          ],
+        },
+      ],
+      copyright: `Copyright © ${new Date().getFullYear()} BackupX · Apache License 2.0`,
+    },
+    prism: {
+      theme: prismThemes.github,
+      darkTheme: prismThemes.dracula,
+      additionalLanguages: ['bash', 'yaml', 'ini', 'json', 'go', 'sql', 'nginx'],
+    },
+  } satisfies Preset.ThemeConfig,
+};
+
+export default config;