[FR]support auto mode

[rexzhang]

The latest version no longer supports separate light/dark theme

[Nedra1998]

I hacked together a bash command to merge the light and dark themes together with prefers-color-scheme to decide between light and dark:

for f in dist/theme-catppuccin-latte-*.css; do
    printf "@media (prefers-color-scheme: dark) {\n%s\n}\n\n@media (prefers-color-scheme: light){\n%s\n}" "$(cat "${f/latte/frappe}")" "$(cat "${f}")" > "out/$(basename "${f/latte/frappe}")"
    printf "@media (prefers-color-scheme: dark) {\n%s\n}\n\n@media (prefers-color-scheme: light){\n%s\n}" "$(cat "${f/latte/macchiato}")" "$(cat "${f}")" > "out/$(basename "${f/latte/macchiato}")"
    printf "@media (prefers-color-scheme: dark) {\n%s\n}\n\n@media (prefers-color-scheme: light){\n%s\n}" "$(cat "${f/latte/mocha}")" "$(cat "${f}")" > "out/$(basename "${f/latte/mocha}")"
done