Improve styling for the list and grid button

I've added the new design system meta as the new parent and changed the old parent to related issue

The main problem in this issue is that there is no component for a toggle button with a pressed and not pressed state yet. in the drupal design system the toggle is only about a visual "switch" (if that is the right term in english). i remembered a discussion we had on the ux channel. in the this comment and the following i've listed a few aspects: https://drupal.slack.com/archives/C1AFW2ZPD/p1704456082112179?thread_ts=... but i guess there need to happen some design work still. and that problem applies to more places in the drupal admin ui not only the list/grid toggle in project browser. one preliminary solution might be to go with a similar design like used in gin, but avoid those extremely rounded corners.

but from my perspective visually it als still not that clear that, in this case grid is the button that is in a pressed state.