fix: resolve Decap CMS media 404s and add Turkish translations

- Fix Decap CMS configuration with proper media folder paths
- Add Turkish translations for sharing interface elements
- Implement smart background handling for transparent logos
- Update image path conversion system for CMS compatibility
- Add comprehensive image optimization with Astro assets
- Update all blog post image paths for consistency

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

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

public/admin/config.yml

@@ -6,8 +6,8 @@ backend:
     - editor
   squash_merges: true
 
-media_folder: 'src/assets/images'
-public_folder: '~/assets/images'
+media_folder: 'public/images'
+public_folder: '/images'
 
 locale: 'tr'