Posts get a nullable image_url. WordPressPublisher now downloads it
and uploads it to WordPress's media endpoint before creating the
post, setting it as featured_media — and rejects publishing (without
touching status) if a blog post has no image set, mirroring the
existing title requirement. Every other network treats it as optional.
Not enforced at save time, same as title — you can still draft an
incomplete WordPress post, it just can't be published until an image
is set. Exposed through the UI form (with a thumbnail/""missing""
indicator in the table), the JSON API, and the Python CLI wrapper.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
