review: format check precedes limits, INVALID_IMAGE/IMAGE_TYPE_MISMATCH as format copy, tile-sized retry control

packages/client/ui-attachment/src/MessageImage.module.css

@@ -58,3 +58,12 @@
   background: var(--dsw-alias-interactive-bg-hover-danger);
   cursor: pointer;
 }
+
+/* A failed tile keeps the 64px grid cell instead of growing to its copy. */
+.error[data-variant='tile'] {
+  width: 64px;
+  height: 64px;
+  padding: 4px;
+  overflow: hidden;
+  border-radius: 16px;
+}