Adresses issue 534

[EfimC-Work]

Summary

Implements support for .NET 6+ DateOnly and TimeOnly types, resolving issue #534.

Changes

• Maps DateOnly to DbType.Date (SQL Server DATE column)
• Maps TimeOnly to DbType.Time (SQL Server TIME column)
• Adds proper serialization/deserialization support
• Includes bidirectional type conversions
• Maintains backward compatibility with .NET Framework 4.8 and .NET Standard 2.0

Files Modified

• Core type mapping and conversion logic
• SQL Server provider adapters
• Test cases for DateOnly/TimeOnly

Testing

• All functioning existing tests pass
• New tests added for DateOnly and TimeOnly types
• Build successful for all target frameworks (net8.0, netstandard2.0, net48)

Backward Compatibility

Uses #if NET6_0_OR_GREATER conditional compilation to maintain compatibility with older frameworks.
Ensured that casts to TimeSpan and DateTime still work.

Build Verification

All changes have been verified to compile successfully

[EfimC-Work]

Third try had a typo in the branch name and could not verify all tests yesterday on my macbook. I think now everything should work as intended

[jonwagner]

Awesome. I will do a review this week.

And since I work off a macbook as well, my position is that I will build Windows-only/old versions but I won't verify them if there are low-risk changes.