docs: Improve navigation and content discoverability in SDS Storybook #3367

Description

As a user of SDS Storybook, I would like to find documentation that is well-organized, easy to navigate, and complete, including onboarding, release information, and usage guidance, so that I can quickly find what I need and work efficiently with SDS, regardless of my role (designer, developer, or stakeholder).

Previous ticket: feat: Audit of SDS Documentation #3171
Figma report: https://www.figma.com/design/YcEmTAljhu3lxTckbzKCf6/Research?node-id=1576-25369

The subtasks bellow will be accessed by the team so we decide which ones move forward.

Where to put the documentation

Storybook and Figma

DoR

• Item has business value
• Item has been estimated by the team
• Item is clear and well-defined
• Item dependencies have been identified