Add ability to configure Pagefind

[AnnsAnns]

What version of starlight are you using?

0.28.2

What is your idea?

Expose the configuration options of Pagefind that you currently can't access without creating your own search component.

Why is this feature necessary?

Pagefind allows you to configure quite a lot of stuff, from giving weights to customize ranking to merging different instances of Pagefind to create cross-site searches.

Sadly all this isn't exposed when using the default Starlight search bar but would greatly help projects that have API Documentation hosted elsewhere, esp. when using API Documentation generators such as Doxygen or want to prioritize different things in their search results.

Do you have examples of this feature in other projects?

• https://docs.zephyrproject.org/latest/
  • Zephyr allows you to search through their Guides (Sphinx) and API documentations (Doxygen) at the same time. While they aren't using Pagefind, this would also be possible in Starlight if the configuration options would be exposed.

Participation

• I am willing to submit a pull request for this feature.

[AnnsAnns]

I was not familiar with Github Discussions therefore did not realize that #1358 existed. Closing this issue in favour of the other one.