feat: support nullable Arrow Device array export

[0ax1]

No description provided.

[codspeed-hq]

Merging this PR will not alter performance

⚠️ Unknown Walltime execution environment detected

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

⚠️ Different runtime environments detected

Some benchmarks with significant performance changes were compared across different runtime environments,
which may affect the accuracy of the results.

Open the report in CodSpeed to investigate

⚡ 1 improved benchmark
❌ 2 regressed benchmarks
✅ 1248 untouched benchmarks

Warning

Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
⚡	Simulation	chunked_varbinview_opt_into_canonical[(1000, 10)]	239.6 µs	203 µs	+17.99%
❌	Simulation	chunked_varbinview_opt_canonical_into[(1000, 10)]	187.5 µs	224.2 µs	-16.38%
❌	Simulation	baseline_lt[16, 65536]	217.6 µs	245.4 µs	-11.34%

Tip

Investigate this regression by commenting @codspeedbot fix this regression on this PR, or directly use the CodSpeed MCP with your agent.

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_{Comparing ad/cudf3-null-masks (2d89c69) with develop (6ddc4d5)}

[robert3005]

I think I originally missed something here. I don't understand why the offseting logic is necessary, that's how the buffers are laid out already