Fix broken links in documentation

[ritoban23]

Fix Broken Links in Documentation

Problem

The documentation contained multiple broken links that were causing 404 errors for users:

• Notion export links with random IDs (e.g., Charges%20in%20plans%201b09b3a59a6880d69013dab788bbe5ea.md)
• Case-sensitive path issues (capital letters in URLs)
• Non-existent file references
• Absolute URLs instead of relative paths
• Images missing alt text for accessibility

Solution

Fixed all broken links and improved documentation quality:

• Removed Notion artifacts: Replaced random ID links with proper documentation paths
• Standardized URLs: Converted to lowercase, relative paths for consistency
• Fixed missing references: Updated links to point to existing files
• Enhanced accessibility: Added descriptive alt text to all images
• Improved maintainability: Consistent link structure across all files

Impact

• 14 files modified with 30+ broken links fixed
• Zero functional links removed - only corrected to working destinations
• Better user experience - no more 404 errors when navigating docs
• Improved accessibility - screen readers can now describe images
• Easier maintenance - consistent URL patterns for future updates

Testing

• All links now point to existing files in the repository
• Image paths verified to be accessible
• Documentation structure maintained while fixing broken references

Closes #45