[python] Remove the no-longer-needed wrapper layers [WIP]

[johnkerl]

These were useful during the cppification project -- they allowed us to migrate from tiledb-py-backed classes to libtiledbsoma-backed classes.

At this point, however, they simply add to the keystroking on all Python dev work. It's time to get rid of them, to save us all from needless copypasta in our development work moving forward.

Notes:

• This PR is not ready for review.
• This is biggish, and not done yet. I am almost always strongly attached to small/split-up PRs, for the benefit of the author as well as the reviewer. This one ... I'm not sure yet how to split it up.

[codecov]

Codecov Report

Attention: Patch coverage is 94.84536% with 5 lines in your changes missing coverage. Please review.

Project coverage is 83.79%. Comparing base (58ca2d0) to head (d411c39).
Report is 6 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3209      +/-   ##
==========================================
+ Coverage   83.19%   83.79%   +0.60%     
==========================================
  Files          51       51              
  Lines        5504     5333     -171     
==========================================
- Hits         4579     4469     -110     
+ Misses        925      864      -61     

Flag	Coverage Δ
python	83.79% <94.84%> (+0.60%)	⬆️

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Components	Coverage Δ
python_api	83.79% <94.84%> (+0.60%)	⬆️
libtiledbsoma	∅ <ø> (∅)