Add sum oracle to the fuzzer and reject samples that have order dependent overflow behaviour

[robert3005]

Fuzzer sum oracle does chunk by chunk aggregation instead of canonicalising and
running aggregate on single chunk

[codspeed-hq]

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

⚡ 2 improved benchmarks
❌ 1 regressed benchmark
✅ 2190 untouched benchmarks
⏩ 218 skipped benchmarks¹

Warning

Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
❌	WallTime	mul_u32_nonnull_avx512	5.5 µs	6.2 µs	-10.24%
⚡	Simulation	decompress[u64, (4000, 1024)]	86.1 µs	70.8 µs	+21.62%
⚡	WallTime	arrow_checked_add_u32_avx2[16384]	21.4 µs	17.7 µs	+21.12%

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/sumfuzzoracle (eff1c5b) with develop (2a5b1a7)}

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. ↩

[joseph-isaacs]

please add a comment. But I think you want to filter >0 and <0 and sum each and it will read better