Enhance article photo handling and API documentation.

- Updated API documentation to reflect changes in article data structure.
- Improved ArticlePhoto component to support dynamic sizing and object fit options.
- Added performance logging for image upload in ArticlePhotosDialog and ArticlePhotoTile components.
- Enhanced ArticleTile to conditionally render photos and adjusted styling for better layout.
- Optimized image preparation process with configurable AVIF encoding speed.

src/components/article/ArticlePhotosDialog.jsx

@@ -61,7 +61,13 @@ class ArticlePhotosDialog extends Component {
     this.setState({ busy: true });
     try {
       const file = await prepareArticlePhoto(rawBlob);
+      const uploadStarted = performance.now();
       const res = await article.uploadImage(articleData.sku, file);
+      console.log('[article-photo] upload', {
+        uploadMs: Math.round(performance.now() - uploadStarted),
+        bytes: file.size,
+        sku: articleData.sku,
+      });
       requireObject(res, 'POST /api/article/:sku/image');
       requireObject(res.image, 'image');
       onArticleUpdated?.(articleWithUploadedPhoto(articleData, res.image));
@@ -136,11 +142,12 @@ class ArticlePhotosDialog extends Component {
         key={photo.fullHash}
         sx={{ position: 'relative', width: 200, height: 200, flexShrink: 0 }}
       >
-        <ArticlePhoto photo={photo} size={200} />
+        <ArticlePhoto photo={photo} size={200} sx={{ position: 'absolute', inset: 0 }} />
         <Box
           sx={{
             position: 'absolute',
             inset: 0,
+            zIndex: 1,
             pointerEvents: 'none',
             display: 'flex',
             flexDirection: 'column',