Puzzmo Theme

Convert the game's colors to use Puzzmo theme tokens, enabling automatic light/dark mode.

Steps

1. Review the theme object received from sdk.gameReady(). Key color tokens:
   • theme.g_bg - Game background
   • theme.g_bgAlt - Alternate background (checkerboard patterns)
   • theme.fg - Foreground text
   • theme.g_textDark - Dark text (on light backgrounds)
   • theme.g_textLight - Light text (on dark backgrounds)
   • theme.key - Primary accent (pink/brand)
   • theme.player - Player color (blue)
   • theme.alt1, alt2, alt3 - Additional accent colors
   • theme.g_key - A variant of key that always has good contrast for dark text
   • theme.error - Error/wrong state color
   • theme.g_unsolved - Unsolved/empty tile color
   • theme.alwaysDark / theme.alwaysLight - Colors that don't change with theme