PPL has NNC_Polyhedron.
Should expose using Sage's Polyhedra classes.
In the context of #20877, NNC polyhedra could play the same role as half-open intervals do in the context of the new piecewise functions.
Normaliz also has the feature of "open facets".
Depends on #32089
Depends on #32159
CC: @kcrisman @kliem @jplab @yuan-zhou
Component: geometry
Issue created by migration from https://trac.sagemath.org/ticket/20879