ABC for convex sets (follow up)

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Depends on #31919

CC:  @kliem @jplab

Component: **geometry**

Branch: **[u/mkoeppe/convex-set-abc-2](https://github.com/sagemath/sagetrac-mirror/tree/u/mkoeppe/convex-set-abc-2)**

_Issue created by migration from https://trac.sagemath.org/ticket/31955_

