chore(driver-adapters): refactor query-engine test executor

[jkomyno]

This is a refactoring PR in preparation for ORM-460:

• I've renamed testd into testd-qe, to indicate that the existing (test) playground is for query-engine only
• I've moved some utilities and setup steps that will be useful for schema-engine-wasm and test-se out of the main executor/src/testd.ts file.
• I've formatted the executor TS files uniformly. We don't need to bother with linting setups here.

This PR can be merged in main right away, without waiting for schema-engine-wasm to be ready.

Additionally, this PR closes:

• ORM-480

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[github-actions]

WASM Query Engine file Size

Engine	This PR	Base branch	Diff
Postgres	2.086MiB	2.084MiB	1.910KiB
Postgres (gzip)	838.105KiB	837.766KiB	347.000B
Mysql	2.049MiB	2.049MiB	-707.000B
Mysql (gzip)	824.325KiB	824.670KiB	-354.000B
Sqlite	1.962MiB	1.962MiB	327.000B
Sqlite (gzip)	788.392KiB	788.648KiB	-262.000B

[codspeed-hq]

CodSpeed Performance Report

Merging #5100 will not alter performance

_{Comparing chore/refactor-driver-adapters-executor (2f520ae) with main (cc0167b)}

Summary

✅ 11 untouched benchmarks