feat: Integrate Docusaurus for documentation and enhance project structure

- Added Docusaurus configuration and initial setup for documentation.
- Created multiple documentation pages covering installation, configuration, and core concepts.
- Implemented a GitHub Actions workflow for automatic deployment of documentation to GitHub Pages.
- Updated .gitignore to exclude Docusaurus build artifacts and dependencies.
- Enhanced README with a link to the online documentation.

docs/src/pages/markdown-page.md

@@ -0,0 +1,7 @@
+---
+title: Markdown page example
+---
+
+# Markdown page example
+
+You don't need React to write simple standalone pages.