Replace dependency @tsconfig/node18 with @tsconfig/node20

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
@tsconfig/node18 (source) → @tsconfig/node20		replacement	18 → 20
@tsconfig/node18 (source) → @tsconfig/node20	devDependencies	replacement	18.2.4 → 20.1.0

⚠️ Renovate's replacement functionality does not currently wire in the release age for a package, so the Minimum Release Age checks can apply. You will need to manually validate the Minimum Release Age for these package(s).

This is a special PR that replaces @tsconfig/node18 with the community suggested minimal stable replacement version.

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