Top Image and bounding box

## Specifications

- **Narrowest data scope**: This will require loading or having the Project already, which requires authentication, but the component only needs the TPEN.activeLine known through the tpen-active-line event.
- TPEN.activeLine is available with the TPEN object and has the full Annotation of the current line. This is available as soon as the tpen-active-line fires. The other needed information will be the Canvas targeted, which should be available in Vault by then as well.
- No other data should be required to load and show the selector.
- **Conditionally include**: It is possible that this component will be on a page that has no active line or any loaded Annotation Page, so it should degrade gracefully. It should continue to listen for the `tpen-active-line` event, but not render anything in particular. It is also useful to consider an event that can suppress this element completely, as some tools may want to hide it temporarily.
- **Consider Size-on-Screen**: This component should be controlled, anticipating that it will always fill the full width of its container, but may try to get too tall if the line is structured poorly or bounds a large page area. A @container query will be the most flexible, as the container may be a grid or flex box.
- **Bookmark Bounding Box**: In addition to showing the above the workspace, there should be a bounding box of the current annotation showing, with a small margin around it. It does not need to completely match 2.8, but here is a reference image: