Release v0.6.0

release: v0.6.0

- add histogram math visualization (cdf, equalization lut, expansion lut)
- add vitest testing infrastructure
- add shared emptystate web component
- improve glass panel contrast (0.70 -> 0.85)
- add css custom properties for glassmorphism theming
- add empty states across workspace, analysis, and imageinfo panels
- add drag-over feedback with file type validation
- add aria tab pattern with keyboard navigation
- add aria attributes to erroralert with focus management
- add tablet responsive breakpoint at 768px
- add disabled button tooltips

- split iimageprocessor into focused interfaces (isp)
- inject processor interfaces into use cases (constructor injection)
- wire composition root with dependency injection