Redesign partners page with clustered layout and filtering

[Copilot]

• Create data/partners.json with all current partners organized into meaningful clusters
• Create layouts/shortcodes/partner_list.html shortcode (similar to publication_list.html)
• Create layouts/shortcodes/partner_filters.html shortcode for filtering by cluster
• Add partner card CSS styles to assets/scss/custom.scss
• Update content/about/partnerships/partnerships.md to use the new data-driven approach
• Fix card styling issues (missing backgrounds, oversized logos)

Summary

This PR redesigns the partners page to address the issue that important partners (like UNESCO) were listed far below defunct ones (like ReplicationWiki). Partners are now:

1. Organized into 7 meaningful clusters drawn from a partners.json file
2. Filterable by category using an interactive filter bar
3. Displayed in a modern card layout consistent with the publications page

Partner Categories (in order of display)

• Global Intergovernmental Organizations (UNESCO - now at the top!)
• Reproducibility Networks (UKRN, GRN, AREN, BrRN, iRISE)
• Open Science Infrastructure (COS, Liberate Science, LMU OSC, etc.)
• Research Communities (SIPS, ReproducibiliTea, BiTS Lab, etc.)
• Education & Training (BITSS, Project TIER, OLS, etc.)
• Early Career & Equity (Metadocencia, ABRIR, JRP, etc.)
• Institutional Partners (Utrecht University)

Screenshots

Fixed Partner Cards with Proper Styling

Early Career & Equity Section (Properly Sized Logos)

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Cluster partners</issue_title>
<issue_description>Currently the list of partners is very long, and some important ones (e.g. UNESCO) are listed far below some that are defunct (ReplicationWiki) - need to revise and cluster that list</issue_description>

Comments on the Issue (you are @copilot in this section)

@LukasWallrich This should be done similar to the new publication page - i.e. with a more modern layout, drawing from a partners.json file. Implement this with a meaningful clustering.

• Fixes Cluster partners #585

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[github-actions]

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[github-actions]

✅ Spell Check Passed

No spelling issues found in this PR! 🎉

[LukasWallrich]

✅ Staging Deployment Status

This PR has been successfully deployed to staging as part of an aggregated deployment.

Deployed at: 2026-01-21 17:33:14 UTC
Staging URL: https://staging.forrt.org

The staging site shows the combined state of all compatible open PRs.

[LukasWallrich]

@copilot this looks terrible. There are no cards, logos have random sizes. Fix

[Copilot]

@copilot this looks terrible. There are no cards, logos have random sizes. Fix
<img width="1257" height="784" alt="image" src="https://github.com/user-attachments/assets/6365c978-08a1-4d1c-9c9c-fb...

Fixed in 5f2beea. Added inline styles as fallback and increased CSS specificity to prevent style overrides. Cards now have proper backgrounds, borders, and logos are correctly constrained to 120x80px max.