Don't require boxing ChunkedArray chunk iterators

[robert3005]

All the callsites don't require it right now and the caller can do it themselves
if they need the type ellision

[codspeed]

Merging this PR will regress 1 benchmark

⚠️ 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.

⚠️ 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

⚡ 5 improved benchmarks
❌ 1 regressed benchmark
✅ 2196 untouched benchmarks
⏩ 218 skipped benchmarks¹

Warning

Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
❌	WallTime	arrow_checked_add_u32_neon[16384]	12.9 µs	20.4 µs	-36.93%
⚡	Simulation	decompress[u64, (4000, 1024)]	87 µs	71.7 µs	+21.34%
⚡	Simulation	allocate_drop_bytes[0]	635.5 ns	527.2 ns	+20.55%
⚡	WallTime	dict_canonicalize_gt_u8_neon[1000000]	560.5 µs	487.6 µs	+14.96%
⚡	WallTime	words_gather_scalar_avx2[65536]	9.4 µs	8.2 µs	+13.69%
⚡	WallTime	mul_u32_nonnull_avx512	6.3 µs	5.6 µs	+12.87%

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 rk/nonboxiter (b79a0bb) with develop (f15c0b8)}

Footnotes

1. 218 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩