[python,c++] Improve error handling in IntIndexer

[bkmartinjr]

Issue and/or context:

IntIndexer would do strange things when given malformed inputs. See for example sc-60689 and sc-60690

IntIndexer also incorrectly handled any arrow array with an offset, and would return incorrect outputs. See sc-60795

Changes:

1. More error checking in pybind-ings, plus tests. The desired parts of the implicit casting are moved up into the Python code where they are more easily managed.
2. Minimal fix to correctly use array offsets (note: this code needs refactoring to use nanoarrow interfaces)

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 86.29%. Comparing base (b30dd60) to head (b6c5785).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3441      +/-   ##
==========================================
+ Coverage   86.22%   86.29%   +0.06%     
==========================================
  Files          55       55              
  Lines        6295     6305      +10     
==========================================
+ Hits         5428     5441      +13     
+ Misses        867      864       -3     

Flag	Coverage Δ
python	86.29% <100.00%> (+0.06%)	⬆️

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

Components	Coverage Δ
python_api	86.29% <100.00%> (+0.06%)	⬆️
libtiledbsoma	∅ <ø> (∅)

[nguyenv]

What is the purpose of adding noconvert?

[bkmartinjr]

What is the purpose of adding noconvert?

It tells pybind to not try and cast, which removes all kinds of unsupported things (i.e., likely errors) from being done implicitly. Pybind will try to cast almost any sequence to an ndarray. If we don't explicitly need that behavior, it is better to just disable it.