chore(website): refresh docs dependencies

[leehack]

Summary

• refresh website Docusaurus packages to 3.10.1
• add the Mermaid ELK layout peer dependency required by the newer Docusaurus Mermaid theme
• scope npm overrides for serialize-javascript@7.0.5 to the Docusaurus bundler's webpack plugin subtrees so the website audit no longer resolves the vulnerable 6.x line
• document the website Node.js floor as Node 20, matching CI docs workflows

Existing issue check

• No matching open issue/PR found for npm audit, Docusaurus dependency, serialize-javascript, or website dependency cleanup.

Test Plan

• git diff --check
• cd website && npm ci
• cd website && npm audit
• cd website && npm ls @docusaurus/core @docusaurus/preset-classic @docusaurus/theme-mermaid @mermaid-js/layout-elk serialize-javascript --depth=4
• cd website && npm run build
• CI: https://github.com/leehack/llamadart/actions/runs/25978785318

Review notes

• Local audit now reports found 0 vulnerabilities for website.
• serialize-javascript@7.0.5 is resolved through scoped npm overrides under copy-webpack-plugin and css-minimizer-webpack-plugin.
• Independent review found no blocking dependency mistakes; the Node 20 engine declaration is included because CI already uses Node 20 for docs workflows.
• Copilot's initial override-scope comment was fixed by replacing the global override with scoped overrides and the outdated thread was resolved.

[Copilot]

Pull request overview

This PR updates the website/ Docusaurus dependency set, adds the required Mermaid ELK layout peer dependency for newer Mermaid theme versions, and introduces an npm override intended to keep serialize-javascript on a non-vulnerable release line while documenting a Node.js 20+ baseline for the docs site.

Changes:

• Bump Docusaurus packages (@docusaurus/core, @docusaurus/preset-classic, @docusaurus/theme-mermaid) to ^3.10.1.
• Add @mermaid-js/layout-elk dependency to satisfy newer Mermaid theme requirements.
• Add npm overrides for serialize-javascript and declare Node >=20 in engines.

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[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 78.50%. Comparing base (8058797) to head (ab53f04).

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #154   +/-   ##
=======================================
  Coverage   78.50%   78.50%           
=======================================
  Files          76       76           
  Lines        9885     9885           
=======================================
  Hits         7760     7760           
  Misses       2125     2125           

Flag	Coverage Δ
unittests	78.50% <ø> (ø)

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[Copilot]

Pull request overview

Copilot reviewed 1 out of 2 changed files in this pull request and generated no new comments.