_attachment_display.html iterates a context variable named
`attachments`, so every caller binds it before the include.
_post_card.html was the one caller that did not: it guarded on
item.attachments but included the partial with nothing bound, so the
gallery looped over whatever `attachments` happened to be in the
surrounding page context and rendered empty. Every post with an image
looked image-less on the feed and on profiles, and on a project page -
where project_detail.html sets `attachments` at template scope for the
project's own files - a devlog card would have rendered the project's
files as its own.
With the image actually reaching the card, render a lone one properly:
a gallery holding exactly one item gets a `single` class and takes the
full content column (max-height 480px, object-fit contain, no hover
scale), matching the original DevPlace. That branch serves the stored
original rather than thumbnail_url, because a thumbnail is 200px on its
longest side and stretching it to the column width is visibly blurry.
Animated GIFs needed no change and now have a test proving it: they
never had a thumbnail to flatten, so they already took the original-file
path and simply render larger.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
