- completely redesigned UI with responsive tailwind styling

- added tabbed interface (editor, analysis results, history)
- implemented local storage for saving analysis history
- added dark/light mode toggle with user preference detection
- enhanced readability metrics with improved visualization
- added advanced settings (reader profile, content type)
- included text analysis recommendations based on metrics
- implemented keyword extraction with frequency counts
- added help modal with detailed usage instructions
- improved text handling with sample/paste/clear options
- enhanced chart visualization with proper scaling

Author: TobiasMue91