Review: thumbnail catalog for 1,400 SimReady assets
Proposed spreadsheet-style catalog with thumbnail, asset name, and main USD link columns. This PR restores the four files removed by the review rollback; no asset packages or access settings change.
Leave this PR unmerged until John explicitly approves publication.
Validation: all 1,400 package rows have matching readable 256 x 256 thumbnails. Hugging Face Datasets loads the catalog with an Image column. Dataset-card metadata validates. Catalog size is 76 MB.
Known live-viewer issue requiring investigation before approval: direct first-rows and paginated rows API calls succeeded, but dataset-level splits/size discovery returned HTTP 500 and the web page showed an unavailable message. This PR preserves the proposed files for review; it does not claim that issue is resolved.
Includes a catalog refresh script. Automatic refresh scheduling is not enabled.