Improve Sphinx AutoAPI Readability

[dougbrn]

This PR removes a lot of bloat in the current sphinx autoapi generation configuration. Submodules had repeated NestedFrame API entries because imported classes were documented by default. This was disabled, and private functions were also disabled from being rendered. Also, removed the lingering PPT example benchmark code which was being rendered.

[github-actions]

Before [5cf1fa5]	After [544553c]	Ratio	Benchmark (Parameter)
34.8±3ms	34.6±2ms	1	benchmarks.AssignSingleDfToNestedSeries.time_run
84.3M	84M	1	benchmarks.NestedFrameAddNested.peakmem_run
8.88±0.1ms	8.88±0.05ms	1	benchmarks.NestedFrameAddNested.time_run
87.3M	87.2M	1	benchmarks.NestedFrameReduce.peakmem_run
6.16±0.05ms	6.06±0.02ms	0.98	benchmarks.NestedFrameQuery.time_run
264M	255M	0.97	benchmarks.AssignSingleDfToNestedSeries.peakmem_run
90.4M	87.5M	0.97	benchmarks.NestedFrameQuery.peakmem_run
1.07±0.01ms	1.03±0.01ms	0.97	benchmarks.NestedFrameReduce.time_run
280M	273M	0.97	benchmarks.ReassignHalfOfNestedSeries.peakmem_run
60.6±2ms	54.9±0.8ms	0.91	benchmarks.ReassignHalfOfNestedSeries.time_run

Click here to view all benchmarks.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 99.43%. Comparing base (5cf1fa5) to head (1f958fb).
Report is 46 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #108      +/-   ##
==========================================
+ Coverage   98.76%   99.43%   +0.66%     
==========================================
  Files          15       14       -1     
  Lines         894      888       -6     
==========================================
  Hits          883      883              
+ Misses         11        5       -6     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[hombit]

Very nice!