Migrate some scripts to Alpine and add 18+ icon

package.json

@@ -16,12 +16,15 @@
     "deploy-lftp": "dotenv tsx scripts/deploy-lftp.ts --"
   },
   "dependencies": {
+    "@astrojs/alpinejs": "^0.4.0",
     "@astrojs/check": "^0.9.3",
     "@astrojs/mdx": "^3.1.6",
     "@astrojs/rss": "^4.0.7",
     "@astrojs/tailwind": "^5.1.0",
     "@astropub/md": "^1.0.0",
     "@tailwindcss/typography": "^0.5.15",
+    "@types/alpinejs": "^3.13.10",
+    "alpinejs": "^3.14.1",
     "astro": "^4.15.5",
     "astro-htaccess": "^0.2.0",
     "astro-pagefind": "^1.6.0",