landingpage: add possibility to navigate to subheaders in getting started guides

[janivo]

Description

The current navigation on the landing page for "Getting Started" guides needs refinement to provide users with a smoother and more interactive experience. The goal is to make the subheaders clickable, allowing users to update the URL with the specific sections within the guides. When users share a link, the guide should open at the designated subheader with an automatic scroll for seamless exploration.

Acceptance Criteria

• Implement the functionality to make subheaders clickable, dynamically updating the URL as users navigate within the "Getting Started" guides.
• Enable links to open the guide at the specified subheader, automatically scrolling to enhance user interaction.

[janivo]

postponed until #1075 is done