Please explain the motivation behind the feature request.

Allow better customization for users which prefer other scheme colors

Describe the solution you'd like

Replace the hardcoded theme names for the light and dark themes with the values from GOOSE_CLI_DARK_THEME and GOOSE_CLI_LIGHT_THEME, if unset, fall back to the current hardcoded values.

Update the documentation to reflect this.

Describe alternatives you've considered

Modifying the color palette of the terminal -> interferes with other programs

Additional context

• I have verified this does not duplicate an existing feature request