Unclear what it means to resize the shelf in the desktop app

It's unclear what it means to resize the shelf in the desktop app, especially since it doesn't have scroll bars in any configuration nor does it enforce aspect ratio.

My suggestion until we have something designed to handle resizing is: force a fixed size of the window that yields a content space with aspect ratio equal to the full shelf (and show the full shelf in that content space).

No file or test is identified. First clarify the intended meaning of resizing the shelf and review the desktop app's shelf and window-sizing behavior; the work is done when the resizing behavior is designed and the full shelf is shown consistently in the available content space.

Written by the indexing model from the issue text.