OZG-4897 move tailwindconfig, add colors, up intellisense, darkmode demoapp

alfa-client/.prettierrc

alfa-client/.vscode/settings.json

alfa-client/apps/demo/src/app/app.component.html

alfa-client/apps/demo/src/app/app.component.ts

alfa-client/apps/demo/src/index.html

alfa-client/apps/demo/src/styles.scss

alfa-client/apps/demo/tailwind.config.js

...lient/libs/design-system/src/lib/tailwind-preset/root.css

.../design-system/src/lib/tailwind-preset/tailwind.config.js