WKB import/export VTables to Arrow

[a10y]

Summary

Part of #7686

Following up on #7722 , which added the WellKnownBinary extension type and handling for exporting to DuckDB vectors.

This PR adds support for import/export to Arrow for the extension type.

Testing

Unit tests are added to exercise both code paths

[codspeed-hq]

Merging this PR will improve performance by 11.85%

⚠️ Unknown Walltime execution environment detected

Using the Walltime instrument on standard Hosted Runners will lead to inconsistent data.

For the most accurate results, we recommend using CodSpeed Macro Runners: bare-metal machines fine-tuned for performance measurement consistency.

⚡ 1 improved benchmark
✅ 1525 untouched benchmarks

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
⚡	Simulation	bitwise_not_vortex_buffer_mut[128]	275.3 ns	246.1 ns	+11.85%

Tip

Curious why this is faster? Comment @codspeedbot explain why this is faster on this PR, or directly use the CodSpeed MCP with your agent.

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_{Comparing aduffy/df-geo (d15353f) with develop (4b6c382)}

[AdamGS]

Looks reasonable