feat(qe): use mimalloc instead of the system allocator

[aqrln]

Experiment with mimalloc to see if it solves our memory fragmenation troubles with JSON and doesn't break napi.

Ref: prisma/prisma#21471

[codspeed-hq]

CodSpeed Performance Report

Merging #5007 will not alter performance

_{Comparing integration/mimalloc (e348b85) with main (b43a787)}

Summary

✅ 11 untouched benchmarks

[github-actions]

WASM Query Engine file Size

Engine	This PR	Base branch	Diff
Postgres	2.708MiB	2.708MiB	0.000B
Postgres (gzip)	1.036MiB	1.036MiB	2.000B
Mysql	2.035MiB	2.035MiB	0.000B
Mysql (gzip)	812.542KiB	812.541KiB	1.000B
Sqlite	1.928MiB	1.928MiB	0.000B
Sqlite (gzip)	770.434KiB	770.435KiB	-1.000B