Reduce allocations when binding scalar parameters

[skuirrels]

Problem

Scalar parameters currently create a temporary duckdb_value, bind it, and dispose it on every execution. That adds wrapper overhead for common values such as numbers, strings, dates, and blobs.

Solution

Use DuckDB's type-specific native bind functions for scalar values. Collections and types that need an exact logical representation keep the existing duckdb_value fallback. byte[] continues to bind as a collection for LIST/ARRAY targets and as BLOB otherwise.

Benchmark

.NET 10 Release, 5 warmups, 10 measured iterations, three scalar parameters:

Metric	Before	After	Change
Prepared execution	23.50 us	22.23 us	-5.4%
Prepared allocation	1,064 B	944 B	-11.3%
Unprepared execution	62.96 us	60.59 us	-3.8%
Unprepared allocation	1,296 B	1,176 B	-9.3%

The stable result is 120 fewer managed bytes per execution; timing is naturally noisier.

Tests

• 6,898 tests passed on the isolated develop-based branch
• Added byte[] LIST and fixed ARRAY regression coverage
• Existing BLOB coverage passes

[codecov]

Codecov Report

❌ Patch coverage is 83.21168% with 23 lines in your changes missing coverage. Please review.
✅ Project coverage is 86.67%. Comparing base (fe2abc5) to head (0aeb7b3).

Files with missing lines	Patch %	Lines
...NET.Data/PreparedStatement/ClrToDuckDBConverter.cs	82.83%	4 Missing and 19 partials ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##           develop     #344      +/-   ##
===========================================
- Coverage    87.59%   86.67%   -0.92%     
===========================================
  Files           77       77              
  Lines         3143     3264     +121     
  Branches       466      482      +16     
===========================================
+ Hits          2753     2829      +76     
- Misses         276      310      +34     
- Partials       114      125      +11     

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