Python test coverage improvements

[wlav]

Python test coverage was reduced in #369 to due refactoring of the code handling various types. This code provides further cleanup by normalizing Python annotations and providing better support for Numpy. This provides two ways for better testing:

• It removes many branches on the C++ side, since it now only needs to deal with canonicalized annotations.
• Many tests can now be moved to the Python side where it's simpler to generate test case.

Additionally, this PR improves the support for numpy types. The test do not strictly use numpy types throughout, in order to provide for tests of C++ types as strings, but from here on out, use of numpy types should be encouraged. The advantages of numpy types are:

• Improved correctness, e.g. use of fully specified np.int64, instead of implementation-defined long.
• Full support from Python code quality tools, instead of having to put #noqa everywhere.

There is some further refactoring to make code more consistent and some Python tests are now enabled even if cppyy is not found (they should never have been conditional on that).

[codecov]

Codecov Report

❌ Patch coverage is 85.71429% with 25 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
plugins/python/src/modulewrap.cpp	72.72%	8 Missing and 13 partials ⚠️
plugins/python/python/phlex/_typing.py	93.65%	4 Missing ⚠️

@@            Coverage Diff             @@
##             main     #399      +/-   ##
==========================================
+ Coverage   83.77%   84.22%   +0.45%     
==========================================
  Files         126      128       +2     
  Lines        3291     3322      +31     
  Branches      583      564      -19     
==========================================
+ Hits         2757     2798      +41     
+ Misses        325      324       -1     
+ Partials      209      200       -9     

Flag	Coverage Δ
unittests	84.22% <85.71%> (+0.45%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
plugins/python/python/phlex/__init__.py	100.00% <100.00%> (ø)
plugins/python/python/phlex/_variant.py	100.00% <100.00%> (ø)
plugins/python/python/phlex/_typing.py	93.65% <93.65%> (ø)
plugins/python/src/modulewrap.cpp	72.42% <72.72%> (+1.11%)	⬆️

... and 4 files with indirect coverage changes

---

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[wlav]

@phlexbot format

[wlav]

@phlexbot python-fix

[github-actions]

No automatic ruff fixes were necessary.

[github-actions]

Format Fixes Applied

✅ cmake-format fixes pushed (commit 0bc921e)
✅ ruff fixes pushed (commit e1b21e5)
✅ YAML formatter fixes pushed (commit 3f775b5)

⚠️ Note: Some issues may require manual review and fixing.

[greenc-FNAL]

Review the full CodeQL report for details.

[greenc-FNAL]

CMake changes look reasonable to me.