feat(event): add mobile sponsor list and refactor landing pages

This commit introduces a new mobile-first sponsor list and restructures the event landing pages. Key changes include:

- A new responsive sponsor list page built with Vue.js and Tailwind CSS, optimized for SEO and on-site viewing.
- The main event index page is now a QR code display for easy access to the mobile list.
- The original landing page is refactored with Tailwind CSS and moved to a new `/landing` directory.
- Umami analytics script is integrated across all pages for usage tracking.

20251108/sponsorList/index.html

@@ -4,6 +4,8 @@
     <meta charset="UTF-8" />
     <meta name="viewport" content="width=device-width, initial-scale=1.0" />
     <title>Sponsor List</title>
+
+    <script src="/analysis.js"></script>
     <script src="https://cdn.jsdelivr.net/npm/@tailwindcss/browser@4"></script>
     <script src="https://unpkg.com/vue@3/dist/vue.global.js"></script>