fix(createlayerinterface): overwrite layer entry when label image is …

…reset

When a label image was set the old label image was replaced but a new layer entry was still being
created. This implied all label images were available but that is not the case. If the label image
is changed the label image layer is simply updated now.

src/createViewer.js

@@ -883,10 +883,16 @@ const createViewer = async (
 
     const imageName =
       layerImageName ?? context.images.selectedName ?? multiscaleLabelImage.name
-    service.send({
-      type: 'ADD_LABEL_IMAGE',
-      data: { imageName, labelImage: multiscaleLabelImage },
-    })
+    const actorContext = context.images.actorContext.get(imageName)
+    if (actorContext?.labelImageName === multiscaleLabelImage.name) {
+      actorContext.labelImage = multiscaleLabelImage
+      service.send({ type: 'LABEL_IMAGE_ASSIGNED', data: imageName })
+    } else {
+      service.send({
+        type: 'ADD_LABEL_IMAGE',
+        data: { imageName, labelImage: multiscaleLabelImage },
+      })
+    }
     publicAPI.setImageInterpolationEnabled(false, imageName)
   })