Match the Share rail's platforms and order to the design

Problem/Motivation

The Horizon Aid "Share" list (LinkedIn/Facebook/X icons next to articles, events, etc.) doesn't match its Figma design's platforms and order, and the recipe's existing webshare.settings: buttons.* config can't fix that: it's only a pre-seed fallback Webshare stops consulting once its own install seeds the webshare_platforms table.

Third round on this thread. !18 added the buttons.* fallback config and flagged the table-seeding limitation. !31 pulled a broken Instagram attempt back out, asking for platforms to be declarable from configuration. This issue is that resolution.

Steps to reproduce

1. Install the Horizon Aid site template.

2. Open any article/event page with a Share block.

3. Observe: LinkedIn, Facebook, X in that order, no Instagram, and the recipe has no working way to change it.

Proposed resolution

Dead end recorded first: webshare.settings: simpleConfigUpdate on buttons.*.weight looks like it should reorder the list, but doesn't — once the webshare_platforms table has rows, that config is never consulted again for rendering. Confirmed by testing directly; removed instead of left in as dead weight.

Real fix: Webshare 2.0.0-beta2 (issue #3591909) added config actions so recipes can manage platforms declaratively. This recipe now declares the rail with one setSocialPlatforms action: exactly Facebook, Instagram, LinkedIn, X, in the design's order, everything else disabled. Instagram renders as a plain link like the other platforms.

No composer change: drupal/webshare already arrives via the required Varbase Blog Base and Varbase Events Base recipes.

Verified live on a Varbase 11 test site in a real browser: the rail renders Facebook, Instagram, LinkedIn, X, enabled and in order, all as normal links.

AI-Generated: Yes

Remaining tasks

✅ File an issue

✅ Addition/Change/Update/Fix

✅ Testing to ensure no regression

➖ Automated unit testing coverage

➖ Automated functional testing coverage

➖ UX/UI designer responsibilities

➖ Readability

➖ Accessibility

➖ Performance

➖ Security

➖ Developer Documentation

➖ User Guide Documentation

❌ Reviewed by human

❌ Code review by maintainers

❌ Full testing and approval

❌ Credit contributors

❌ Review with the product owner

➖ Release notes snippet

❌ Release

User interface changes

The Share list matches the design's platforms and order: Facebook, Instagram, LinkedIn, X.

API changes

N/A

Data model changes

N/A

Release notes snippet

N/A