Add TUI styled output with lipgloss

[CalvinAllen]

Summary

Add TUI (Text User Interface) styling to enhance the visual experience of the dtvem CLI using the charmbracelet/lipgloss library.

Changes

New TUI Package (internal/tui/)

Created a separate internal/tui package (distinct from internal/ui) to keep lipgloss dependencies out of the shim binary:

• styles.go - Color palette, text styles, box styles, and indicator constants
• table.go - Reusable table component with:
  • Rounded borders
  • Centered titles that span all columns
  • Optional hidden headers
  • Configurable minimum width
  • Active row highlighting (green)
  • Proper width calculation with ANSI codes

Updated Commands

• list - Table with Version/Status columns, runtime name as title
• list-all - Table with checkmark indicators, paging support (--limit flag), global/local status indicators
• current - Table with Runtime/Version/Status columns, "Active Versions" title
• version - Styled info box
• where - Simplified to title + info box
• --help - Custom usage function with two styled tables (header + available commands)
• --version - Intercepted to use our custom version command output

Other Improvements

• Hidden completion command until implemented
• Fixed duplicate error messages on unknown flags
• Consistent table widths across help output (95 characters)

Color Palette

• Primary (Cyan): Titles, headers, runtime names
• Secondary (Magenta/Pink): Version numbers
• Success (Green): Active versions, checkmarks
• Warning (Orange): Warning indicators
• Error (Red): Cross marks, errors
• Muted (Gray): Borders, secondary text

Benefits

• Improved visual organization with bordered tables
• Clearer indication of active/global/local versions
• Consistent styling across all commands
• No impact on shim binary size (separate package)