refactor(allocator): Arena::alloc_with write through a &mut MaybeUninit

[overlookmotel]

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[overlookmotel]

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• perf(allocator): keep allocator pointers in registers across multiple allocations #24928
• refactor(allocator): allocation handle slow path via closure #24924
• refactor(allocator): Arena::alloc_with write through a &mut MaybeUninit #24923 👈 (View in Graphite)
• docs(allocator): improve doc comments for Arena methods #24922
• main

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[codspeed-hq]

Merging this PR will not alter performance

✅ 67 untouched benchmarks
⏩ 9 skipped benchmarks¹

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_{Comparing om/07-24-refactor_allocator_arena_alloc_with_write_through_a_mut_maybeuninit_ (0a33089) with om/07-24-docs_allocator_improve_doc_comments_for_arena_methods (87a7e17)}

Footnotes

1. 9 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. ↩