[c++] Column abstraction: SOMAGeometryColumn, part 3

[XanthosXanthopoulos]

This PR introduces the SOMAGeometryColumn concrete class that implement a spatial index WKB (Well-Known Binary) column. A set of internal TileDB dimensions are used to provide the index mechanics as well as a TileDB Attribute to hold the geometry data encoded in a WKB blob.

[johnkerl]

@XanthosXanthopoulos thanks for working on this! The split-up makes this PR much easier to review.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 86.30%. Comparing base (eabdb30) to head (a426c7a).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3427      +/-   ##
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+ Coverage   86.25%   86.30%   +0.04%     
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  Files          55       55              
  Lines        6359     6359              
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+ Hits         5485     5488       +3     
+ Misses        874      871       -3     

Flag	Coverage Δ
python	86.30% <ø> (+0.04%)	⬆️

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Components	Coverage Δ
python_api	86.30% <ø> (+0.04%)	⬆️
libtiledbsoma	∅ <ø> (∅)

[johnkerl]

Saying either 'core domain', 'core current domain', 'soma domain', or 'soma maxdomain' is absoutely crucial for avoiding confusion. Saying 'domain' might mean any one of these four, and so it ambiguous. I requested these changes the last time; I'm still requesting them this time.

I know the names are confusing and that's why we must be absolutely vigilant to help out our co-workers, in the present and in the future, by being very clear.

[johnkerl]

Thank you @XanthosXanthopoulos !