A lip picked on a face that isn't a shelled body's rim, such as the Sample Plate's top
face with its two holes and the boss standing on it, ran its band round the largest inner
edge. That was the boss's foot, so the band stood against the boss's wall and the join
failed with a boolean error about curved faces.
The band now goes round the face's opening (an inner edge with no material just over the
face inside it). A rim face that has a smaller hole in it still works. A face whose inner
edges are only where other features stand on it, or whose openings are alike in size (a
plate's holes), is refused with a plain message that names the rim face it needs.
Fixes#892.
Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
