Enhance UI theming and component styling for improved consistency

Commit notes

- Updated theme configuration in root.tsx to include new font families and color settings for better visual coherence. - Modified BpmControl, GainMeter, TransportControls, and StepGrid components to utilize monospace font for specific text elements, enhancing readability. - Refactored PatternControls to replace Shuffle icon with ShuffleIcon for consistency in icon usage and improved visual presentation.