aggregate fns to have grouped aggregate kernels for sum and count

[onursatici]

Summary

aggregate functions to be able to do grouped aggregations before the fallback that slices group by group.

Implements count for all arrays and sum for primitives.

API Changes

Grouped aggregate kernels now receive a single GroupedArray enum, covering ListViewArray and FixedSizeListArray, instead of exposing separate methods for each list representation

[joseph-isaacs]

This seems like a good idea

[codspeed-hq]

Merging this PR will improve performance by 73.54%

⚠️ 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.

⚡ 8 improved benchmarks
❌ 5 regressed benchmarks
✅ 1506 untouched benchmarks

Warning

Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
❌	Simulation	bitwise_not_vortex_buffer_mut[128]	216.9 ns	275.3 ns	-21.19%
❌	Simulation	bitwise_not_vortex_buffer_mut[1024]	278.6 ns	336.9 ns	-17.31%
❌	Simulation	chunked_varbinview_opt_canonical_into[(1000, 10)]	191.4 µs	226.8 µs	-15.6%
❌	Simulation	chunked_varbinview_opt_into_canonical[(1000, 10)]	205.7 µs	241.4 µs	-14.81%
❌	Simulation	bitwise_not_vortex_buffer_mut[2048]	342.2 ns	400.6 ns	-14.56%
⚡	Simulation	count_i32_clustered_nulls	672.6 µs	55.2 µs	×12
⚡	Simulation	sum_i32_clustered_nulls	581.2 µs	72.5 µs	×8
⚡	Simulation	sum_i32_nullable_all_valid	350.4 µs	74.2 µs	×4.7
⚡	Simulation	count_varbinview	259.4 µs	76.1 µs	×3.4
⚡	Simulation	chunked_bool_canonical_into[(1000, 10)]	46.9 µs	31.8 µs	+47.75%
⚡	Simulation	chunked_varbinview_canonical_into[(100, 100)]	311.3 µs	274.4 µs	+13.47%
⚡	Simulation	chunked_varbinview_into_canonical[(100, 100)]	363.2 µs	327.2 µs	+11%
⚡	Simulation	encode_varbin[(1000, 2)]	177.1 µs	160.3 µs	+10.51%

Tip

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_{Comparing os/grouped-agg (ef4ae99) with develop (068e1ad)}