- complete redesign of photo filter editor with dark mode support

- add new adjustment features: exposure, sepia, noise, sharpen
- implement image transformation tools: rotation and flip
- add compare feature to preview original vs edited image
- improve UI with tooltips and responsive design
- enhance canvas rendering with proper scaling and centering
- add drag-and-drop support for images
- implement keyboard shortcuts for common operations
- replace `fabric.js` dependency with native canvas API
- improve loading states and error handling

Author: TobiasMue91