feat: initialize Vue application with main components and styles

- Added App.vue as the main application component with a structured layout.
- Created main.js to bootstrap the Vue application and mount it to the DOM.
- Introduced styles.css for global styling, including responsive design and theming.
- Removed outdated HTML files (stats.html, towns.html) and Python script (statsprocess.py) as part of the migration to a new Vue-based architecture.
- Added Vite configuration (vite.config.js) for building the Vue application.

public/robots.txt

@@ -0,0 +1,5 @@
+User-agent: *
+Allow: /
+Disallow: /stats/*.json
+
+Sitemap: https://bailuyuan.lunadeer.cn/sitemap.xml