test: Benchmark slowdown of element-wise list comparison

[Marius Merkle (MariusMerkleQC)]

Motivation

See this comment.

Changes

Adds a benchmark test on (long) list columns (20 elements each). The column has an integer data type, so no tolerance-based comparison is necessary. We call _compare_sequence_columns as soon as there's a list/array anywhere in the data type tree, independent of the inner type, and this is ~5-6 times slower than using _eq_missing directly.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 100.00%. Comparing base (cccfad4) to head (c6e108f).
⚠️ Report is 15 commits behind head on main.

Additional details and impacted files

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  Lines          758       758           
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[Copilot]

Pull request overview

Adds a performance-focused test to quantify the slowdown of element-wise list comparison vs eq_missing() for list columns with non-tolerance inner types, supporting follow-up optimization work around _compare_sequence_columns.

Changes:

• Import internal comparison utilities/constants needed to call condition_equal_columns() directly.
• Add a new performance regression-style test comparing eq_missing() vs element-wise list comparison timing.

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[Oliver Borchert (borchero)]

Thanks :)