✨ feat(homepage): allow hiding posts listing

[welpo]

Summary

Added the possibility of hiding posts on the main page.

To achieve this, do not set paginate_by nor section_path in the [extra] section of an _index.md file.

Related issue

Resolves #316.

Changes

• Added conditional logic to determine the order of displaying sections (projects or posts) on the main page.
• Updated the <main> tag to conditionally apply the appropriate CSS class based on the presence of sections.
• Included dynamic construction of template paths and used them for conditional inclusion of sections.

Accessibility

No changes.

Type of change

• Bug fix (fixes an issue without altering functionality)
• New feature (adds non-breaking functionality)
• Breaking change (alters existing functionality)
• UI/UX improvement (enhances user interface without altering functionality)
• Refactor (improves code quality without altering functionality)
• Documentation update
• Other (please describe below)

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Checklist

• I have verified the accessibility of my changes
• I have tested all possible scenarios for this change
• I have updated theme.toml with a sane default for the feature
• I have made corresponding changes to the documentation:
  • Updated config.toml comments
  • Updated theme.toml comments
  • Updated "Mastering tabi" post in English
  • (Optional) Updated "Mastering tabi" post in Spanish
  • (Optional) Updated "Mastering tabi" post in Catalan