By: Michael Lynch <git@mtlynch.io>
Keep imported thumbnails required without inventing photo files Tinybeans photo exports include thumbnail URLs in metadata, but they do not include local thumbnail files on disk. Video exports do include thumbnail files. This change keeps photo thumbnail filenames distinct by parsing `blobs.t`, but stops requiring a local photo thumbnail path during Tinybeans export parsing. The importer still guarantees that every imported media entry has a thumbnail: photos generate one from the original image and videos copy the exported thumbnail file. The tests now reflect the real export shape instead of creating synthetic photo thumbnail files under testdata.