feat(registry): add lower thirds catalog blocks

[kiyeonjeon21]

Summary

• Add the News Ticker lower-third block from feat(registry): add lower thirds catalog blocks #1134.
• Take over the podcast/interview lower-thirds pack from feat(registry): add podcast/interview lower-thirds pack (10 blocks) #1689 and the BILD-style lower third from feat(registry): add lower-third-bild #1276, with original contributors preserved as coauthors.
• Add the missing generated catalog pages from docs(catalog): add missing flowchart-vertical and vfx-liquid-glass pages #1525 for flowchart-vertical and vfx-liquid-glass.
• Add a dedicated Lower Thirds catalog group and update the catalog index/nav so these overlays are discoverable together.

Preview Assets

• Generated PNG/MP4 docs previews for the new lower-third blocks.
• Uploaded the generated preview media to the public docs CDN.
• Verified the uploaded media URLs return 200.

Verification

• bunx oxfmt --check ...
• JSON parse check for registry/registry.json, docs/docs.json, and docs/public/catalog-index.json
• git diff --cached --check
• npx mintlify validate
• HyperFrames lint + validate for all added/updated lower-third blocks
• Local Mintlify page check for /catalog/blocks/news-ticker

[kiyeonjeon21]

news-ticker-preview.mp4

[kiyeonjeon21]

Signed and force-pushed the existing commit. No content changes.

[miguel-heygen]

@kiyeonjeon21 can you solve merge conflicts? I'll stamp after that

[miguel-heygen]

Updated this PR on top of current main and resolved the stale generated-file conflicts.

Changes in a76d8f89:

• Adds the news-ticker registry block and manifest.
• Adds the generated Mintlify catalog page.
• Wires the block into registry/registry.json, docs/docs.json, and docs/public/catalog-index.json under Social Overlays.

Local verification:

• bunx oxfmt --check registry/blocks/news-ticker/news-ticker.html registry/blocks/news-ticker/registry-item.json docs/catalog/blocks/news-ticker.mdx docs/docs.json docs/public/catalog-index.json registry/registry.json
• JSON parse check for registry/docs manifests
• npx hyperframes lint and npx hyperframes validate against a temp project using news-ticker.html as index.html
• npx hyperframes snapshot --at 0.5,3.5,6.5 --describe false for visual smoke coverage

GitHub checks are running on the updated branch.

[miguel-heygen]

Took this PR over and broadened it to close the related open catalog-block work in one branch.

Folded in:

• feat(registry): add lower thirds catalog blocks #1134: news-ticker
• feat(registry): add podcast/interview lower-thirds pack (10 blocks) #1689: podcast/interview lower-thirds pack (lt-* blocks)
• feat(registry): add lower-third-bild #1276: lower-third-bild
• docs(catalog): add missing flowchart-vertical and vfx-liquid-glass pages #1525: generated catalog pages for flowchart-vertical and vfx-liquid-glass

Also added a dedicated Lower Thirds catalog group, updated docs/public/catalog-index.json, generated/uploaded CDN PNG+MP4 previews for the new lower-third pages, and preserved original contributor attribution via coauthor trailers.

Local verification:

• bunx oxfmt --check ...
• JSON parse for registry/docs/catalog index
• git diff --cached --check
• npx mintlify validate
• HyperFrames lint + validate for all added/updated lower-third blocks
• Mintlify page check for /catalog/blocks/news-ticker