chore: bump version to 5.5.1 and update dependencies

- Upgrade version from 5.5.0 to 5.5.1
- Update third-party dependencies: algolia, disqusjs, docsearch, fancybox, fontawesome, mermaid
- Replace Twitter with X in share configurations
- Enable CDN version numbers by default
- Fix shuoshuo page JSON security with safeJSON helper
- Improve image lazy loading regex to handle minified HTML
- Fix search result HTML structure and styling
- Add margin-top to search result numbering for better alignment

scripts/helpers/page.js

@@ -157,3 +157,12 @@ hexo.extend.helper.register('getVersion', () => {
   const { version } = require('../../package.json')
   return { hexo: hexo.version, theme: version }
 })
+
+hexo.extend.helper.register('safeJSON', data => {
+  // Safely serialize JSON for embedding in <script> tags
+  return JSON.stringify(data)
+    .replace(/</g, '\\u003c')
+    .replace(/>/g, '\\u003e')
+    .replace(/\u2028/g, '\\u2028')
+    .replace(/\u2029/g, '\\u2029')
+})