The sanitize_svg_icon before_validation callback called icon.download,
but Active Storage uploads pending blobs in before_save — so at
before_validation time the file only existed in the request tempfile,
not at the configured storage path. Read from the pending attachable
(UploadedFile / IO hash) instead. Guards against the recursive callback
that icon.attach would otherwise trigger by tracking the cleaned
attachable by object identity. Bumps to 0.13.1.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
