Update documentation to reflect current project structure

- Rename CLAUDE.MD to CLAUDE.md for correct case-sensitive formatting
- Update file structure diagrams across all documentation files
- Document standard Astro src/ directory structure (layouts, pages)
- Add 404.astro custom error page to documentation
- Include robots.txt and sitemap integration in docs
- Update current status to reflect completed features:
  - Custom 404 page with themed styling
  - Sitemap integration for SEO
  - Accessibility improvements (ARIA labels, semantic HTML)
- Update code examples to use proper import paths from src/
- Mark completed TODO items (404 page, sitemap, accessibility)

All documentation now accurately reflects the standard Astro project
structure with layouts in src/layouts/ and pages in src/pages/.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

TODO.md

@@ -1,10 +1,14 @@
 # Cozy Den - Tasks & TODO
 
 ## Current Status
-✅ Initial project structure created
+✅ Initial project structure created (proper src/ directory)
 ✅ Landing page with all main sections
 ✅ Docker deployment setup
 ✅ Responsive design
+✅ Custom 404 page
+✅ Sitemap integration
+✅ robots.txt
+✅ Accessibility improvements (ARIA labels, semantic HTML)
 
 ## Immediate Next Steps
 
@@ -17,7 +21,7 @@
 ### Optional Enhancements
 
 #### Short Term
-- [ ] Add a custom 404 page
+- [x] Add a custom 404 page
 - [ ] Add favicon variants for different platforms (apple-touch-icon, etc.)
 - [ ] Add Open Graph meta tags for social media sharing
 - [ ] Add animation on scroll for sections
@@ -90,9 +94,9 @@ Pull repository data from Gitea API and display:
 - [ ] Consider breaking large components into smaller ones
 - [ ] Add comments for complex CSS
 - [ ] Set up automated testing if site grows
-- [ ] Add accessibility audit
+- [x] Add accessibility audit
 - [ ] Optimize images if any are added
-- [ ] Consider adding a sitemap.xml
+- [x] Consider adding a sitemap.xml
 
 ## Performance Optimization