Added Documentation homepage

[VictorPuga]

Summary

What this change addresses / expected UX

Adds a home (/ ) experience inspired by https://developer.apple.com/documentation: a centered hero plus two card grids for top-level documentation and tutorials. Users now land on a concise, styled index that matches the sidebar’s top-level navigation (only roots, with proper icons), hides empty sections, and adapts to light/dark themes.

Before

After

Note: The UI/layout can be changed based on suggestions in this PR. The screenshot is just an initial implementation

Implementation overview

• src/views/Index.vue: reuse DocumentationLayout with a filtered Navigator (top-level only); hero text now uses new i18n keys (documentation.hero.title/copy); cards use TopicTypeIcon; responsive 3/2/1 grid; hero width responsive (50% on desktop, full on smaller screens); simplified themed styling.
• Routing unchanged; home remains “/”.
• i18n: added documentation.hero.title and documentation.hero.copy to locale files (en-US, ja-JP, zh-CN, ko-KR).
• Tests: new tests/unit/views/Index.spec.js covers hero i18n, navigator top-level-only data, and hiding empty sections.
• Styles cleaned to rely on theme tokens for color/shadows and responsive spacing.

Inspiration explicitly taken from https://developer.apple.com/documentation ’s documentation landing layout.

Dependencies

None

Testing

Steps:

1. Build the documentation archive
2. Run the renderer
3. Visit the server index (http://localhost:8080/)

Checklist

Make sure you check off the following items. If they cannot be completed, provide a reason.

• Added tests
• Ran npm test, and it succeeded
• Updated documentation if necessary

[marinaaisa]

Thank you for your contribution, @VictorPuga !

Before we can consider merging a change like this, we'd need to discuss it in the Swift forums first.

Could you create a forum post, like this one, that outlines:

• What problem does this solve? What's the use case or pain point you're addressing?
• How does your solution work? What data does it use to generate the page?
• What are the alternatives? Have you considered other approaches, and why is this one preferable?
• How does it compare to existing functionality? Specifically, how does this differ from or improve upon the landing pages that DocC already creates for merged/combined archives? (live demo)
• Customization options: To what extent can developers customize the content and appearance of this page?

This will help us evaluate whether this aligns with DocC's goals and ensure we've thought through the implications before committing to support it. Looking forward to the discussion!

[VictorPuga]

I have not yet experimented with merged documentation archives, so I will attempt to do so to provide a more detailed response to your questions.

I will create the thread in the forums shortly.

[VictorPuga]

Please refer to the forums thread: https://forums.swift.org/t/documentation-homepage/83704

[VictorPuga]

@marinaaisa it seems like the conversation on the thread has gone stale. What would you suggest for us to get a decision on this proposal?