perf: remove unneeded scalar_at and valid_at and use arrays instead

[joseph-isaacs]

We often pull out and decompress array when doing is_valid in a loop, this PR instead uses execute_mask once and then operates on a Mask in the loop.

We could later come along and replace this Mask::value(&self) method with a packed chunk iterator.

[codspeed-hq]

Merging this PR will improve performance by 20.92%

⚠️ 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.

⚡ 13 improved benchmarks
❌ 2 regressed benchmarks
✅ 1508 untouched benchmarks

Warning

Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
❌	Simulation	decompress_rd[f64, (100000, 0.0)]	845.9 µs	1,024.1 µs	-17.4%
❌	Simulation	decompress_rd[f32, (100000, 0.0)]	499.5 µs	586.5 µs	-14.85%
⚡	Simulation	extend_from_array_non_zctl_overlapping[(10000, 8)]	4 ms	2.3 ms	+70.67%
⚡	Simulation	extend_from_array_non_zctl_overlapping[(1000, 8)]	452.9 µs	287 µs	+57.79%
⚡	Simulation	chunked_bool_canonical_into[(1000, 10)]	46.7 µs	31.7 µs	+47.23%
⚡	Simulation	varbinview_zip_block_mask	3.7 ms	2.9 ms	+27.49%
⚡	Simulation	bitwise_not_vortex_buffer_mut[128]	275.3 ns	216.9 ns	+26.89%
⚡	Simulation	chunked_varbinview_canonical_into[(1000, 10)]	197.9 µs	161.9 µs	+22.26%
⚡	Simulation	extend_from_array_non_zctl_overlapping[(1000, 32)]	948.6 µs	782.4 µs	+21.24%
⚡	Simulation	bitwise_not_vortex_buffer_mut[1024]	336.9 ns	278.6 ns	+20.94%
⚡	Simulation	chunked_varbinview_into_canonical[(1000, 10)]	213.6 µs	177.3 µs	+20.48%
⚡	Simulation	bitwise_not_vortex_buffer_mut[2048]	400.6 ns	342.2 ns	+17.05%
⚡	Simulation	decompress_rd[f64, (100000, 0.01)]	981.6 µs	845.5 µs	+16.11%
⚡	Simulation	decompress_rd[f64, (100000, 0.1)]	981.6 µs	845.4 µs	+16.1%
⚡	Simulation	varbinview_zip_fragmented_mask	6.9 ms	6.2 ms	+12.4%

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 ji/row-accessor-remove (6626533) with develop (f2148d4)}