Enable automatic light/dark mode

Signed-off-by: Nick Slowinski <nick@nick-slowinski.de>

docusaurus.config.ts

@@ -169,6 +169,11 @@ const config: Config = {
       theme: prismThemes.github,
       darkTheme: prismThemes.dracula,
     },
+    colorMode: {
+      defaultMode: 'dark',
+      disableSwitch: false,
+      respectPrefersColorScheme: true,
+    },
   } satisfies Preset.ThemeConfig,
 };