Feat: Horizontal posters for search and recommendations.

[ByAyzen]

Since horizontal posters were only available on the main page, I wanted to bring this support to the search and recommendations sections as well. To not break multi search, I disabled it there and only applied it to extension search. I also used @prerelease tag to be sure it doesn't break the stable version.

Parameters for implementing to extensions:

@Prerelease
open val hasHorizontalSearch: Boolean = false
@Prerelease
open val hasHorizontalRecommendations: Boolean = false

I'm not completely sure about these two parameters because they can feel confusing; I can agree to change them. I could place them directly into search and new*****LoadResponse similar to how mainpage does it.

AI Usage

I used AI for implementing this idea. After that, I checked and cleaned up the issues.

Tests

I tested on both prerelease and debug versions. Tested for 2 days and didn't have any problems.

**Two comparison images below;

Search
Recommendation

[fire-light42]

Good feature, but needs more @Prerelease annotations and a small change in MainAPI 👍

[fire-light42]

These should rather be a property of SearchResponseList akin to HomePageList, to be consistent and allow for flexible results.

[fire-light42]

This can be made backwards compatible since it uses a builder function.

[ByAyzen]

I wasn't quite sure about these two properties either. Thanks for the feedback.