Adds Starlight to documentation tools category

[delucis]

Starlight is a documentation website tool similar to other tools in that category.

GitHub repo: https://github.com/withastro/starlight (5.8k stars)
Website: https://starlight.astro.build/

Examples of websites built using Starlight:

• https://developers.cloudflare.com/
• https://cli.netlify.com/
• https://sst.dev/docs/
• https://tauri.app/
• https://biomejs.dev/
• https://docs.fontawesome.com/
• https://docs.orama.com/
• https://contribute.freecodecamp.org/
• https://docs.astro.build/

Pre-submission checklist:

Please check each of these after submitting your pull request:

• Are you only including a repo_url if your project is 100% open source? If so, you need to pick the single best GitHub repository for your project, not a GitHub organization.
• Have you picked the single best (existing) category for your project?
• If submitting a tool, is your project closed source or, if it is open source, does your project have at least 100 GitHub stars?
• Does it follow the other guidelines from the new entries section?
• Have you included a URL for your SVG or added it to hosted_logos and referenced it there?
• Does your logo clearly state the name of the project/product and follow the other logo guidelines?
• Does your project/product name match the text on the logo?
• Have you verified that the Crunchbase data for your organization is correct (including headquarters and LinkedIn)?

[anajsana]

LGTM. Thanks for including this tool!