refactor: partition bound expressions

[joseph-isaacs]

Superseded by #9157

GitHub marked this PR indirectly merged when the stack was reordered and its rewritten head became an ancestor of #9126's branch. The partition change is not in develop; #9157 is the replacement lower PR against develop.

The reordered stack is:

1. refactor: partition bound expressions #9157 — partition bound expressions
2. refactor: propagate bound expressions through layouts #9126 — propagate bound expressions through layouts

[codspeed-hq]

Merging this PR will not alter performance

✅ 1842 untouched benchmarks
⏩ 55 skipped benchmarks¹

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_{Comparing ji/bound-expr-partition (579f1e0) with develop (8c5f663)²}

Footnotes

1. 55 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. ↩

2. No successful run was found on ji/bound-expr-stack (b771484) during the generation of this report, so develop (8c5f663) was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩