Fix pushed cast nullability conversion

[gatesn]

Use DataFusion's physical expression nullability when converting pushed casts into Vortex expressions. This keeps target-field metadata from turning nullable physical casts into non-null Vortex runtime assertions.

[AdamGS]

should we replace the current convert?

[codspeed-hq]

Merging this PR will improve performance by 13.89%

⚠️ 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.

⚡ 16 improved benchmarks
❌ 2 regressed benchmarks
✅ 1563 untouched benchmarks

Warning

Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
❌	Simulation	chunked_varbinview_canonical_into[(100, 100)]	223.8 µs	258.7 µs	-13.49%
❌	Simulation	chunked_varbinview_opt_canonical_into[(100, 100)]	304.7 µs	339.7 µs	-10.3%
⚡	Simulation	decompress_rd[f64, (10000, 0.01)]	139 µs	108.4 µs	+28.22%
⚡	Simulation	decompress_rd[f64, (10000, 0.1)]	139.3 µs	108.7 µs	+28.17%
⚡	Simulation	decompress_rd[f64, (10000, 0.0)]	138.9 µs	108.4 µs	+28.14%
⚡	Simulation	chunked_varbinview_opt_canonical_into[(1000, 10)]	206.7 µs	170.3 µs	+21.33%
⚡	Simulation	take_10k_first_chunk_only	271.7 µs	226.9 µs	+19.72%
⚡	Simulation	take_10k_dispersed	285.5 µs	240.8 µs	+18.53%
⚡	Simulation	decompress_rd[f32, (100000, 0.0)]	583.6 µs	495.6 µs	+17.76%
⚡	Simulation	decompress_rd[f32, (10000, 0.1)]	91 µs	77.7 µs	+17.14%
⚡	Simulation	decompress_rd[f32, (10000, 0.01)]	90.8 µs	77.7 µs	+16.81%
⚡	Simulation	decompress_rd[f32, (10000, 0.0)]	91 µs	78.2 µs	+16.41%
⚡	Simulation	bitwise_not_vortex_buffer_mut[128]	244.4 ns	215.3 ns	+13.55%
⚡	Simulation	patched_take_10k_adversarial	260.3 µs	230.2 µs	+13.05%
⚡	Simulation	chunked_varbinview_into_canonical[(100, 100)]	307.3 µs	272 µs	+12.98%
⚡	Simulation	patched_take_10k_first_chunk_only	303.4 µs	273.2 µs	+11.06%
⚡	Simulation	bitwise_not_vortex_buffer_mut[1024]	304.7 ns	275.6 ns	+10.58%
⚡	Simulation	patched_take_10k_dispersed	317.5 µs	287.3 µs	+10.49%

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 ngates/fix-cast-nullability (1f97053) with develop (02e085f)}