Dev/astro migration

[mag1cfrog]

This pull request includes updates to Node.js version, site configuration, component logic, and styling for better compatibility, maintainability, and functionality. The most important changes include upgrading the Node.js version, modifying the site base URL, improving the HeaderLink component's type safety and logic, and removing an unused import.

Environment and configuration updates:

• .github/workflows/deploy.yml: Upgraded Node.js version from 18 to 22 in the GitHub Actions workflow to ensure compatibility with newer features and dependencies.
• astro.config.mjs: Updated the site configuration to include the base path /spark-tuning-notes/ directly in the URL, simplifying the configuration and resolving potential path issues.

Component improvements:

• src/components/HeaderLink.astro: Refactored the HeaderLink component to:
  • Enforce href as a string in the Props interface for better type safety.
  • Dynamically resolve the correct URL, accounting for the base path in production.
  • Simplify and improve the active-link logic for accurate path comparison.
  • Streamline class combination logic for better readability.

Code cleanup:

• src/pages/about.astro: Commented out an unused import (AboutHeroImage) to reduce unnecessary code.