[Storybook] Create new background image

[RichKummer]

Follow-on to #6758

Based on the research in the previous story, we can now begin crafting a new Storybook background image. This image should align with the visual styles of the Carbon core and Carbon Labs Storybook designs. If there were Figma files used for the Carbon core and Carbon Labs images, use those as a starting point.

The background image should highlight Carbon for IBM Products components and patterns. Display the things that make our offering unique!

Check out the Figma files for the backgrounds:

• Carbon Labs
• Carbon React

Tasks

• Create a proposed new design for the background that follows Carbon core/Labs approach
• Play back to the team
• Create follow-on issues