Add the ability to force dark or light mode colors for CLI output,
overriding the automatic terminal background detection.
Changes:
- Add CLITheme field to TownSettings for persisting preference
- Add GetThemeMode() and HasDarkBackground() to ui package for
theme detection with GT_THEME env var override
- Add ApplyThemeMode() to explicitly set lipgloss dark background
- Add 'gt theme cli' subcommand to view/set CLI theme preference
- Initialize theme in CLI startup (persistentPreRun)
- Add comprehensive tests for theme mode functionality
Usage:
- gt theme cli # show current theme
- gt theme cli dark # force dark mode
- gt theme cli light # force light mode
- gt theme cli auto # auto-detect (default)
- GT_THEME=dark gt status # per-command override
Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>