When using configure-based (i.e. non-Windows) Python installations, if more than one build variant is installed to the same prefix, some files in the bin and lib/pkgconfig directories currently are installed with the same name by each variant, with potentially unpredictable and undesired results.

See issue #122402 for background and details.

This PR addresses identified issues for installs of non-default build variants {v}), i.e debug (d), free-threading (t), and free-threading debug (td), by changing:

• make altinstall for d, t, and td variants:
  • do not install python3.x and python3.x-config
  • install idle3.x, pydoc3.x as idle3.x{v}, pydoc3.x{v}
  • do not install lib/pkgconfig python-3.x-embed.pc and python-3.x.pc
• make install for d, t, and td variants:
  • install python3, python3-config as python3{v}, python3{v}-config
  • install idle3, pydoc3 as idle3{v}, pydoc3{v}
  • install lib/pkgconfig python3-embed.pc, python.pc as python3{v}-embed.pc, python3.pc

The PR also eliminates similar conflicts in the Unix Tools symlinks installed for macOS frameworks builds.

• Issue: Eliminate conflicts between build variants installed to a common prefix #122402