By: Michael Lynch <git@mtlynch.io>
Extract generateThumbnail into images.GenerateSquareThumbnail Moves thumbnail logic into a new images package with a buffer-based API (io.Reader/io.Writer) and a sizeInPx parameter, decoupling it from file I/O. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>