Add rendered example to multiple files section of Download component

[fern-api]

Summary

Adds a rendered example (highlight-frame with a clickable button) to the "Multiple files as ZIP" section of the Download component page, matching the style of the existing single file section.

The rendered example uses real, publicly accessible files hosted via raw.githubusercontent.com so the download button produces a working ZIP. Two small plant-themed text files (fern-care-guide.txt, watering-schedule.txt) are added alongside the existing all-about-ferns.pdf as downloadable assets. The code block below the rendered example uses the same URLs for consistency.

Updates since last revision

• Updated the code block to use the same raw.githubusercontent.com URLs as the rendered example, so the two are consistent (previously the code block used generic example.com placeholder URLs).

Review & Testing Checklist for Human

• Verify the "Download plant care guides" button renders correctly in the highlight-frame on the preview page
• After merge: click the download button and confirm a plant-care-bundle.zip is produced containing all 3 files (all-about-ferns.pdf, fern-care-guide.txt, watering-schedule.txt). The raw GitHub URLs point to @main, so the new .txt files won't resolve until this PR is merged.
• Consider whether the long raw.githubusercontent.com URLs in the code block are acceptable for documentation, or if shorter/generic URLs would be preferable for readability
• Confirm the two new .txt files don't cause unexpected docs build side effects (e.g., being indexed as pages)

Notes

• The rendered example's download will not fully work in preview because the two new .txt files are not yet on the main branch. The existing all-about-ferns.pdf URL will resolve, but the other two will fail until merge.

Link to Devin session: https://app.devin.ai/sessions/08bb6c8e95804d04960abb2cd07c4335

[github-actions]

🌿 Preview your docs: https://fern-preview-4eed1547-8484-4202-a6e6-58459f4918da.docs.buildwithfern.com/learn

Here are the markdown pages you've updated:

• learn/docs/writing-content/components/download

[fern-api]

Requested by: devin
Slack thread: View conversation