- Add ErrorBoundary component for React error handling
- Create animated error pages (403, 404, 500, 502, 503)
- Implement ErrorAnimation component with seven-segment display
- Add apiClient (axios) and apiFetch (fetch) wrappers with automatic error page redirects
- Migrate critical API calls to use new error handling
- Update font from Roboto to Open Sans across all components
- Remove unused CLIENT_URL from docker-compose files
- Rename 404Page.css to ErrorPage.css for consistency
- Add comprehensive ERROR_HANDLING.md documentation
