Hardcoded app mock-ups (litmus-t78w)
Simple app mock-ups: hardcoded terminal output rendered with theme colors (fake git diff, ls output, shell prompt).
Summary of Changes
- Created widgets/util.rs with shared to_ratatui_color() helper
- Created widgets/mockups.rs with MockupsWidget rendering hardcoded git diff and ls -la output using theme colors
- Updated widgets/swatches.rs to use the shared helper from util
- Updated widgets/mod.rs to export both widgets
- Updated main.rs with View enum (Swatches/Mockups) and Tab key cycling between views