Curate README usage gallery

[Mine77]

Summary

• split Prompt into Presentation, Poster, and Social Media tables with three examples each
• expand More from the Gallery into a curated 3x3 grid
• visually review candidates and exclude broken placeholders, clipped copy, missing imagery, and unfinished layouts
• keep the English and Chinese READMEs aligned
• rely on the existing local-link check for Gallery asset validation instead of duplicating every filename in the test

Verification

• npm test
• git diff --check
• 18 unique Gallery assets referenced in each README
• verified selected WebP files visually and by file type