Truncate long author lists on front page cards

[lukepayyapilli]

Summary

• Add CSS line-clamp truncation for author lists on front page and search results.
• Apply .card-authors class to both homepage_content_list.html and content_list.html.
• Update demo fixtures to include a project with 14 authors to demonstrate truncation.

Approach

Uses CSS-only truncation with line-clamp to limit author lists to a single line with ellipsis. This is simpler than a Django filter approach and provides consistent rendering across all cards.

Screenshots

Fixes #2462

[lukepayyapilli]

@tompollard - let me know if this works for the issue. Thanks!

[tompollard]

Thanks Luke! Right now it looks like we are applying two independent filters (CSS line clamp and Django filter). This could lead to inconsistent rendering (sometimes et al, sometimes not). I think we should probably just apply one.

I'm okay with either, but I think my preference is the CSS method with the ellipsis, for simplicity. The "et al" is good for formal citations, but perhaps more than we need here.

Side note and we can do in a separate PR if needed, but we should probably apply the filtering method to the search results too, to avoid this: https://physionet.org/content/. It's in the template here:

physionet-build/physionet-django/search/templates/search/content_list.html

Lines 10 to 13 in 7a5ab9f

	<p class="text-muted">
	{% for author in published_project.author_list %}
	{{ author.get_full_name }}{% if not forloop.last %}, {% endif %}
	{% endfor %}

[lukepayyapilli]

updated @tompollard!

[tompollard]

Looks great, thanks Luke.