feat(docs): Docusaurus with auto-deployment to GitHub pages

[evgheni7]

Issue summary:

For provider users documentation proposed to use Docusaurus framework.

Todo:

• Setup default Docusaurus 3.8 in root of repository.
• Make docs plugin to be loaded by default route.
• Make dark/light modes linked to OS system settings (if not by default).
• Make dark background color: #232734
• Add Overlock favicon from main website.
• Activate local search plugin.
• Setup GitHub action for build and deploy it on "main" branch push to GitHub Pages, according to this guide:
  https://docusaurus.io/docs/deployment#deploying-to-github-pages
• Make it linked to domain: https://docs.overlock.network