Add list_sum expression

[mhk197]

Adds a vortex.list.sum scalar function: the sum of each row's list elements, one output row per input row — the equivalent of DuckDB's list_sum() and DataFusion's array_sum().

Note that list entries that are empty or all null need to be nullified. However, GroupedAccumulator returns 0 in these cases, so we need to either:

1. Change the behavior of GroupedAccumulator and grouped sum (or even sum) kernels or
2. Do a second pass of list element validity and sizes, construct a mask for the sums, and apply it.

The first option is probably best but can be applied in a followup PR.

[codspeed-hq]

Merging this PR will improve performance by 12.58%

⚠️ 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

⚡ 4 improved benchmarks
❌ 1 regressed benchmark
✅ 1614 untouched benchmarks
🆕 11 new benchmarks
⏩ 42 skipped benchmarks¹

Warning

Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
❌	Simulation	chunked_varbinview_into_canonical[(1000, 10)]	169.7 µs	206.1 µs	-17.65%
⚡	Simulation	bitwise_not_vortex_buffer_mut[128]	273.6 ns	215.3 ns	+27.1%
⚡	Simulation	chunked_varbinview_canonical_into[(1000, 10)]	190.5 µs	154.6 µs	+23.17%
⚡	Simulation	bitwise_not_vortex_buffer_mut[1024]	333.9 ns	275.6 ns	+21.17%
⚡	Simulation	bitwise_not_vortex_buffer_mut[2048]	427.8 ns	369.4 ns	+15.79%
🆕	Simulation	fsl_sum_large	N/A	65.2 ms	N/A
🆕	Simulation	fsl_sum_medium	N/A	728.1 µs	N/A
🆕	Simulation	fsl_sum_small	N/A	57 µs	N/A
🆕	Simulation	list_sum_large	N/A	135.7 ms	N/A
🆕	Simulation	list_sum_medium	N/A	1.1 ms	N/A
🆕	Simulation	list_sum_nullable_elements_large	N/A	496 ms	N/A
🆕	Simulation	list_sum_nullable_elements_medium	N/A	4.9 ms	N/A
🆕	Simulation	list_sum_small	N/A	144 µs	N/A
🆕	Simulation	listview_sum_large	N/A	108.1 ms	N/A
🆕	Simulation	listview_sum_medium	N/A	900.2 µs	N/A
🆕	Simulation	listview_sum_small	N/A	74 µs	N/A

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 mk/list-sum-expr (8aad0cc) with develop (11f15a9)}

Footnotes

1. 42 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. ↩