Added deprecation warnings to all modules not previously prefixed with an underscore

[agronholm]

This was done to discourage anyone from importing wheel.

[agronholm]

This can only be merged after a new setuptools release (v70.1 or v71.0) and when the necessary code has been merged to packaging and made it into a release.

[codecov]

Codecov Report

Attention: Patch coverage is 74.05330% with 185 lines in your changes missing coverage. Please review.

Project coverage is 70.00%. Comparing base (1e00742) to head (c341c7f).
Report is 21 commits behind head on main.

Files with missing lines	Patch %	Lines
src/wheel/_bdist_wheel.py	54.24%	140 Missing ⚠️
src/wheel/_macosx_libfile.py	92.81%	12 Missing ⚠️
src/wheel/_metadata.py	92.30%	7 Missing ⚠️
src/wheel/metadata.py	0.00%	6 Missing ⚠️
src/wheel/wheelfile.py	0.00%	5 Missing ⚠️
src/wheel/_wheelfile.py	96.66%	4 Missing ⚠️
src/wheel/_cli/__init__.py	25.00%	3 Missing ⚠️
src/wheel/bdist_wheel.py	0.00%	3 Missing ⚠️
src/wheel/macosx_libfile.py	0.00%	3 Missing ⚠️
src/wheel/__main__.py	0.00%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #620      +/-   ##
==========================================
- Coverage   71.03%   70.00%   -1.04%     
==========================================
  Files          13       17       +4     
  Lines        1084     1100      +16     
==========================================
  Hits          770      770              
- Misses        314      330      +16     

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[agronholm]

This should actually be done when packaging contains all the necessary APIs so that nobody should have to import anything from wheel.