sage.geometry.polyhedron.backend_cdd: Go through sage.features for _cdd_executable #32645
Description
This is so that the Sage library becomes fully functional even when not being run from within sage-env (which sets PATH).
To test (when cddlib is not present in the system but installed as SPKG):
venv/bin/python3 -c 'from sage.all import *; print(Polyhedron(vertices=[[1.123456789012345, 2.123456789012345]], base_ring=RDF))'
Depends on #31296
Component: refactoring
Author: Matthias Koeppe
Branch/Commit: 14d3a65
Reviewer: Travis Scrimshaw
Issue created by migration from https://trac.sagemath.org/ticket/32645