Add public column metadata to Cursor

[lovetodream]

closes #31

[codecov]

Codecov Report

Attention: Patch coverage is 67.92453% with 51 lines in your changes missing coverage. Please review.

Project coverage is 74.80%. Comparing base (4c3bd5e) to head (77efa3c).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main      #33      +/-   ##
==========================================
- Coverage   76.53%   74.80%   -1.73%     
==========================================
  Files         111      111              
  Lines       13251    13270      +19     
==========================================
- Hits        10141     9926     -215     
- Misses       3110     3344     +234     

Files	Coverage Δ
...onnectionStateMachine/ConnectionStateMachine.swift	70.39% <ø> (-0.03%)	⬇️
...ectionStateMachine/ExtendedQueryStateMachine.swift	74.76% <ø> (-2.66%)	⬇️
.../Messages/Coding/OracleBackendMessageDecoder.swift	87.82% <100.00%> (+0.21%)	⬆️
...Messages/Coding/OracleFrontendMessageEncoder.swift	77.03% <ø> (-2.63%)	⬇️
...acleNIO/Messages/OracleBackendMessage+Accept.swift	100.00% <100.00%> (ø)
Sources/OracleNIO/OracleRow.swift	0.00% <ø> (ø)
Sources/OracleNIO/OracleRowSequence.swift	98.41% <ø> (ø)
Sources/OracleNIO/OracleRowStream.swift	56.18% <ø> (-1.89%)	⬇️
Sources/OracleNIO/VariadicGenerics.swift	88.29% <ø> (ø)
Tests/OracleNIOTests/CapabilitiesTests.swift	100.00% <100.00%> (ø)
... and 3 more

... and 10 files with indirect coverage changes

[lovetodream]

messed up commits, continuing here #34