Improve image instrumentation, not hidden `image` should be needed

[mhaack]

Currently we need https://github.com/mhaack/special-project/blob/74d72cfd3f390d959d2e95033dfb1d258d64e097/component-models.json#L68-L87 which is odd. Without that the user will see two image input fields in the side panel, like:

This is caused because the image is instrumented with data-aue-prop="image" which is different from the css selector we have in the model.