Restore app catalog icons

[akirk]

Summary

• add per-blueprint app-meta.json sidecars for app catalog-only icon metadata
• merge app-meta.json into apps.json during reindexing
• restore the app icons removed by the latest reindex job without adding unsupported fields to blueprint.json

Testing

• npm run validate:my-wordpress-json
• env GITHUB_BRANCH=trunk CHANGED_FILES=$'blueprints/ai-assistant/app-meta.json\nblueprints/apiary-press/app-meta.json\nblueprints/chat-to-blog/app-meta.json\nblueprints/memex/app-meta.json\nblueprints/personal-crm/app-meta.json\nblueprints/post-collection/app-meta.json\nblueprints/rss-reader/app-meta.json\nblueprints/wordpress-courses/app-meta.json' npm run validate:pr-blueprints
• node JSON.parse check for all app-meta.json files

[github-actions]

Test using WordPress Playground

The changes in this pull request can be previewed and tested using a WordPress Playground instance.

WordPress Playground is an experimental project that creates a full WordPress instance entirely within the browser.

Some things to be aware of

• All changes will be lost when closing a tab with a Playground instance.
• All changes will be lost when refreshing the page.
• A fresh instance is created each time one of the links below is clicked.

For more details about these limitations and more, check out the Limitations page in the WordPress Playground documentation.

Blueprint previews

• Open apiary-press in WordPress Playground